Hard X-ray flux from low-mass stars in the Cygnus OB2 Association (2009)
Caramazza, M., Drake, J. J., Micela, G., Flaccomio, E.
Context. The Cygnus OB2 association, the central engine of the Cygnus X star-forming region, is the subject of an extensive INTEGRAL Key Project that will accumulate 6Ms of observations. Analysis of...
Results from DROXO. II. - [Ne II] and X-ray emission from Rho Ophiuchi young stellar objects (2009)
Flaccomio, E., Stelzer, B., Sciortino, S., Micela, G., Pillitteri, I., Testi, L.
The infrared [Ne II] and [Ne III] fine structure lines at 12.81um and 15.55um are predicted to trace the circumstellar disk gas subject to X-ray heating and ionization. We investigate the origin of...
Lopez-Santiago, J., Micela, G., Montes, D.
The associations and moving groups of young stars are excellent laboratories for investigating stellar formation in the solar neighborhood. Previous results have confirmed that a non-negligible...
The X-ray emission from Z CMa during an FUor-like outburst and the detection of its X-ray jet (2009)
Stelzer, B., Hubrig, S., Orlando, S., Micela, G., Mikulasek, Z., Schoeller, M.
Accretion shocks have been recognized as important X-ray emission mechanism for pre-main sequence stars. Yet the X-ray properties of FUor outbursts, events that are caused by violent accretion, have...
De Becker, M., Blomme, R., Micela, G., Pittard, J. M., Rauw, G., Romero, G. E., ...
Several colliding-wind massive binaries are known to be non-thermal emitters in the radio domain. This constitutes strong evidence for the fact that an efficient particle acceleration process is at...
Simbol-X core science in a context (2009)
Fiore, F., Arnaud, M., Briel, U., Cavazzuti, E., Cledassou, R., Counil, J. L., ...
Guarcello, M. G., Micela, G., Damiani, F., Peres, G., Prisinzano, L., Sciortino, S.
Context: the observations of the proplyds in the Orion Nebula Cluster, showing clear evidence of ongoing photoevaporation, have provided a clear proof about the role of the externally induced...
X-ray observations of IC348 in light of an updated cluster census (2008)
Stelzer, B., Micela, G., Flaccomio, E., Sciortino, S.
IC348 is an excellent laboratory for studies of low-mass star formation being nearby, compact and rich. A Chandra observation was carried out early in the satellite's lifetime. The extensive new data...
Scelsi, L., Sacco, G., Affer, L., Argiroffi, C., Pillitteri, I., Maggio, A., ...
We have analyzed optical spectra of 25 X-ray sources identified as potential new members of the Taurus molecular cloud (TMC), in order to confirm their membership in this SFR. Fifty-seven candidates...
The X-ray luminosity of solar-mass stars in the intermediate age open cluster NGC 752 (2008)
Giardino, G., Pillitteri, I., Favata, F., Micela, G.
AIMS. While observational evidence shows that most of the decline in a star's X-ray activity occurs between the age of the Hyades (~8 x 10^8 yrs) and that of the Sun, very little is known about the...
An X-ray survey of low-mass stars in Trumpler 16 with Chandra (2008)
Albacete-Colombo, J. F., Damiani, F., Micela, G., Sciortino, S., Harnden Jr, F. R.
We identify and characterize low-mass stars in the ~3 Myr old Trumpler 16 (Tr16) region by means of a deep Chandra X-ray observation, and study their optical and near-IR properties. We compare X-ray...
Circumstellar Disks in the Outer Galaxy: the Star-Forming Region NGC 1893 (2008)
Caramazza, M., Micela, G., Prisinzano, L., Rebull, L., Sciortino, S., Stauffer, J. R.
It is still debated whether star formation process depends on environment. In particular it is yet unclear whether star formation in the outer Galaxy, where the environmental conditions are,...
The X-ray cycle in the solar-type star HD 81809 (2008)
Favata, F., Micela, G., Orlando, S., Sciortino, S., Hall, J.
(abridged) Our long-term XMM-Newton program of long-term monitoring of a solar-like star with a well-studied chromospheric cycle, HD 81809 aims to study whether an X-ray cycle is present, along with...
Circumstellar disks in the outer galaxy : the star-forming region NGC 1893 (2008)
Caramazza, M., Micela, G., Prisinzano, L., Rebull, L., Sciortino, S., Stauffer, J. R.
Context. It is still debated whether star formation process depends on environment. In particular it is yet unclear whether star formation in the outer Galaxy, where the environmental conditions are,...
X-ray properties of protostars in the Orion Nebula (2008)
Prisinzano, L., Micela, G., Flaccomio, E., Stauffer, J. R., Megeath, T., Rebull, L., ...
The origin and evolution of the X-ray emission in very young stellar objects (YSOs) are not yet well understood because it is very hard to observe YSOs in the protostellar phase. Using COUP data, we...
The stellar population of the Rosat North Ecliptic Pole survey. II. Spectral analysis (2008)
Affer, L., Micela, G., Morel, T.
X-ray surveys allow to identify young, main-sequence stars in the solar neighborhood. Young, stellar samples, selected according to their activity, can be used to determine the stellar birthrate in...
Will Be Inserted, F. Favata, R. Mewe, N. S. Brickhouse, R. Pallavicini, G. Micela, ...
We present a SAX/LECS X-ray observation of the active binary Capella, the first coronal source observed in the SAX Guest Investigator program. The analysis of this observation, performed using the...
Astronomy Astrophysics manuscript no. aa040202 April 8, 2004 (2008)
Doi Will Be, B. Stelzer, G. Micela, R. Neuhäuser
We report on a 30 ksec XMM-Newton observation of the central region of the Cha I star forming cloud. The field includes a substantial fraction of the known pre-main sequence population of Cha I...
Will Be Inserted, F. Favata, G. Micela, S. Sciortino
We present determinations of the lithium abundance (through observations of the Li i 6707.8 A line) in a sample of main sequence stars with spectral types ranging from late F down to M0, selected...
Will Be Inserted, F. Favata, G. Micela, S. Sciortino, F. Morale
We present spectroscopic determinations of the Fe abundance in a sample of K-type stars selected from the Xray flux-limited Einstein Extended Medium Sensitivity Survey. These stars have been shown to...
Will Be Inserted, A. Marino, G. Micela, G. Peres
We have systematically analyzed X-ray variability of dM stars. Our data base is the sample of all dM stars listed in the CNS3 (Gliese & Jahreifi 1991) catalog which have been observed with the...
Astronomy Astrophysics manuscript no. H4467 July 8, 2003 (2008)
Doi Will Be, J. Sanz-forcada, A. Maggio, G. Micela
The young active star AB Dor (K1 IV-V) has been observed 16 times in the last three years with the XMM-Newton and Chandra observatories, totalling 650 ks of high-resolution X-ray spectra. The XMM/RGS...
Astronomy Astrophysics manuscript no. 3630 August 8, 2005 (2008)
Doi Will Be, F. Damiani, G. Micela, S. Sciortino
We present a Chandra ACIS-I X-ray observation of the region near the Herbig early-Be star MWC 297, where we detect a tight group of point X-ray sources. These are probably physically associated to...
Will Be Inserted, F. Morale, G. Micela, F. Favata, S. Sciortino
We present the results of a uvby-fi photometric study of a sample of active late-type stars (F--K) selected from the Einstein Extended Medium Sensitivity Survey. Our work shows the presence in the...
Damiani Prisinzano Micela, F. Damiani, L. Prisinzano, G. Micela, S. Sciortino
We present a combined X-ray, optical and IR (2MASS) study of NGC 6530, complementing our previous studies of this cluster. We consider di#erent indicators of IR excesses, taken as indicator of...
Aa 406, 629--638 (2003) Doi: 10.1051/0004-6361:20030689 (2008)
Eso Astronomy Astrophysics, A. Marino, G. Micela, G. Peres, S. Sciortino
We present a comprehensive analysis of X-ray variability of the late-type (dF7-dM) Pleiades stars, detected in all ROSAT-PSPC observations; X-ray variations on short (hours) and medium (months) time...
Astronomy Astrophysics manuscript no. 2516 June 16, 2006 (2008)
Doi Will Be, A. Marino, G. Micela, I. Pillitteri, G. Peres
We present the characteristics of the X-ray variability of stars in the cluster NGC 2516 as derived from XMM-Newton/EPIC/pn data. The X-ray variations on short (hours), medium (months), and long...
Astronomy Astrophysics manuscript no. h4301 June 19, 2003 (2008)
Doi Will Be, B. Stelzer, N. Huélamo, S. Hubrig, H. Zinnecker, G. Micela
We present the first results from a series of Chandra observations carried out with the aim to examine the origin of X-ray emission in main-sequence late B-type stars. X-ray detections of late-B and...
A Deep X-Ray Survey Of The Pms Population Of The Upper Sco-Cen Association (2008)
Sciortino Damiani, S. Sciortino, F. Damiani, G. Micela, F. Favata
han previously reported. A recent X-ray surveys, based on the ROSAT All-Sky Survey (RASS) data, studied a much larger areas of the sky, but with the same limiting sensitivity as the older Einstein...
X-Ray And Optical Observations Of The Star Forming Region Ngc 2264 (2008)
Flaccomio Sciortino, E. Flaccomio, S. Sciortino, G. Micela, F. Damiani, F. Favata, ...
. We present a ROSAT High Resolution Imager (HRI) observation of the star forming region NGC 2264. The analysis has detected more than 40 X-ray sources with Lx in the range 10 30 \Gamma10 31 erg/sec....
Astronomy Astrophysics manuscript no. paperadleo September 26, 2002 (2008)
Doi Will Be, J. Sanz-forcada, G. Micela, Inaf Osservatorio, Astronomico Palermo, G. S. Vaiana, ...
All the Extreme Ultraviolet Explorer (EUVE) observations of AD Leo, totalling 1.1 Ms of exposure time, have been employed to analyze the corona of this single M dwarf. The light curves show a well de...
Astronomy Astrophysics manuscript no. (2008)
Will Be Inserted, A. Marino, G. Micela, G. Peres, S. Sciortino
We have analyzed the X-ray variability of dF7-dK2 stars in the solar neighborhood detected with the pointed ROSAT-PSPC observations. Our data base is the sample of all stars listed in the CNS3...
E. Flaccomio, F. Damiani, G. Micela, S. Sciortino, F. R. Harnden, S. S. Murray, ...
Using the results of our rst paper on the Chandra HRC observation of the Orion Nebula Cluster (ONC), here we explore the relation between the coronal activity of its 1-Myr-old pre-main sequence...
Geometry Diagnostics of a Stellar Flare from Fluorescent X-rays (2008)
Testa, P., Drake, J. J., Ercolano, B., Reale, F., Huenemoerder, D. P., Affer, L., ...
We present evidence of Fe fluorescent emission in the Chandra HETGS spectrum of the single G-type giant HR 9024 during a large flare. In analogy to solar X-ray observations, we interpret the observed...
Simbol-X capability of detecting the non-thermal emission of stellar flares (2008)
Argiroffi, C., Micela, G., Maggio, A.
We investigate the capability of detecting, with Simbol-X, non-thermal emission during stellar flares, and distinguishing it from hot thermal emission. We find that flare non-thermal emission is...
X-ray variability of NGC 2516 stars in the XMM-Newton observations (2008)
Marino, A., Micela, G., Pillitteri, I., Peres, G.
We present the characteristics of the X-ray variability of stars in the cluster NGC2516 as derived from XMM-Newton/EPIC/pn data. The X-ray variations on short (hours), medium (months), and long...
Fiore, F., Arnaud, M., Briel, U., Cappi, M., Comastri, A., Decourchelle, A., ...
Simbol-X is a French-Italian mission, with a participation of German laboratories, for X-ray astronomy in the wide 0.5-80 keV band. Taking advantage of emerging technology in mirror manufacturing and...
The nearest X-ray emitting protostellar jet (HH 154) observed with Hubble� (2008)
R. Bonito, F. Favata, G. Micela, G. Peres, A. A. Djupvik, ...
Received, accepted Context. The jet coming from the YSO binary L1551 IRS5 is the closest astrophysical jet known. It is therefore a unique laboratory for studies of outflow mechanisms and of the...
X-ray properties of protostars in the Orion Nebula (2007)
Prisinzano, L., Micela, G., Flaccomio, E., Stauffer, J. R., Megeath, T., Rebull, L., ...
The origin and evolution of the X-rays in very young stellar objects (YSOs) are not yet well understood since it is very hard to observe YSOs in the protostellar phase. We study the X-ray properties...
A. Maggio, S. Orlando, F. Favata, G. Micela, G. Peres, S. Sciortino
We present the results of extensive sets of simulations, performed to evaluate the diagnostic potential of the analysis of EPIC spectra. 1.
G. Micela, S. Sciortino, F. Favata, R. Pallavicini, J. Pye
ABSTRACT. We present preliminary results from two deep HRI ROSAT exposures on the i Sculptoris open cluster. This cluster, younger than the Pleiades, has photometric indicators that seem to imply a...
G. Micela, S. Sciortino, F. R. Harnden, V. Kashyap, R. Rosner, F. Damiani, ...
A&A manuscript no. (will be inserted by hand later) Your thesaurus codes are:
ASTRONOMY AND ASTROPHYSICS (2007)
F. Favata, G. Micela, S. Sciortino
A&A manuscript no. (will be inserted by hand later) Your thesaurus codes are:
X-ray observations of the young open cluster Blanco 1 (2007)
G. Micela, S. Sciortino, F. Favata, R. Pallavicini, J. Pye
A&A manuscript no. (will be inserted by hand later) Your thesaurus codes are:
LOOP MODELING OF X-RAY CORONAE: SOLAR-TYPE STARS IN YOUNG CLUSTERS AND ASSOCIATIONS (2007)
A. Maggio, G. Micela, G. Peres
ABSTRACT. The disk-integrated X-ray emission from late-type stars originates from hot coronal plasmas most likely confined in closed magnetic structures, of the kind clearly observed on the Sun. The...
ASTRONOMY AND ASTROPHYSICS (2007)
F. Favata, G. Micela, S. Sciortino
A&A manuscript no. (will be inserted by hand later) Your thesaurus codes are:
A Source Detection Method for ROSAT/PSPC X-Ray Images based on Wavelet Transforms (2007)
F. Damiani, A. Maggio, G. Micela, S. Sciortino
. We have developed a method based on wavelet transforms (WT) to detect sources in ROSAT PSPC X-ray images. The WT, evaluated at a set of scale parameters a, detects efficiently both point-like and...
X-Ray Emitting Pms Stars In Upper Sco-Cen: The X-Ray Faint Population (2007)
Favata Sciortino Damiani, F. Favata, S. Sciortino, F. Damiani, G. Micela
. We have performed an X-ray-based survey of the upper Sco-Cen star forming region, combining a deep ROSAT HRI pointing performed explicitly for this purpose with shallower ROSAT PSPC and HRI...
Lithium abundance in a volume limited sample of nearby main sequence G and K stars (2007)
Favata Micela And, F. Favata, G. Micela, S. Sciortino
. We present observations of the Li I 6707.8 A line in a volume limited sample of main sequence stars of spectral types ranging from late F down to M0, selected from the Gliese catalog of nearby...
X-Ray Variability And Rotation In The Pleiades Cluster (2007)
Micela And, G. Micela, S. Sciortino, F. R. Harnden, R. Rosner
Introduction The issue of coronal emission variability is one of the current problems of stellar physics. The Sun exhibits large variability in X-rays with amplitude of more than one order of...
A Reduction and Analysis Pipeline for ROSAT PSPC Data (2007)
G. Mackie, Mackie Fabbiano, F. R. Harnden, M. Barbera, F. Bocchino, ...
. We describe a pipeline to reduce and analyze ROSAT Position -Sensitive Proportional Counter (PSPC) archive data. The pipeline is based on an IRAF Command Language (CL) script, that primarily...
Determination of the length of coronal loops from the decay of X-ray flares (2007)
Ii Stellar, F. Reale, G. Micela
. We illustrate a procedure to estimate the length of stellar coronal loops from the decay of X-ray flares observed with ROSAT/PSPC. As we did in the first paper of this series for solar flares, we...
The Evolutionary Status Of High-Lithium, High-Activity Cool Dwarfs (2007)
Favata Micela, F. Favata, G. Micela, S. Sciortino
. We have used the newly available Hipparcos parallaxes to study the evolutionary status of a number of high-lithium, high-activity late-type dwarfs found in X-ray based surveys, i.e. the Einstein...
Astronomy And Astrophysics (2007)
February Bvri, E. Flaccomio, G. Micela, S. Sciortino, F. Favata, C. Corbally, ...
. The pre-main sequence (PMS) population in the mass range between ß 0:2 and ß 3M fi in southern part of the star-forming region NGC 2264 has been studied, determining both the Initial Mass...
X-Ray Emission, Stellar Populations and Determination of IMF (2007)
Sciortino Micela, S. Sciortino, G. Micela, F. Damiani, E. Flaccomio, Osservatorio Astronomico, ...
X-ray observations allow investigation of the relation among coronal emission level and other stellar parameters, still poorly considered in the standard evolutionary models, such as rotation rate,...
Astron. Nachr./AN 32X (200X) X, XXX--XXX Stellar X-Ray surveys and Galaxy structure (2007)
Received date will be inserted by the editor; accepted date will be inserted by the editor Abstract. Soft X-ray surveys are very effective to study low-mass stellar populations in our Galaxy. Indeed...
ASTRONOMY AND ASTROPHYSICS (2007)
F. Favata, G. Micela, S. Sciortino
A&A manuscript no. (will be inserted by hand later) Your thesaurus codes are:
Discovery of X-ray emission from the proto-stellar jet (2007)
F. Favata, J. Drake, L Irs (hh, Fabio Favata, G. Micela, ...
Abstract. We have for the rst time detected X-ray emission associated with a proto-stellar jet, on the jet emanating from L1551 IRS5. The IRS5 proto-star is hidden beyond a very large absorbing...
Mon. Not. R. Astron. Soc. 000, 000-000 (0000) Printed 25 April 2001 (MN L A T E X style (2007)
Le Rosat Medium, J. E. Morley, K. R. Briggs, J. P. Pye, F. Favata, G. Micela, ...
We have performed a moderately deep soft X-ray (0.1-2 keV) survey of the Galactic Plane using pointed observations with the ROSAT Position Sensitive Proportional Counter (PSPC). The survey is more...
Astronomy Astrophysics manuscript no. (2007)
Will Be Inserted, N. Pizzolato, P. Ventura, A. Maggio, G. Micela, S. Sciortino
We present an extensive study on the dependence of the convective turnover time (conv ) on the stellar metallicity and age for main-sequence stars of masses 0.6-1.6 M . To this aim we have used and...
Astronomy Astrophysics manuscript no. (2007)
Will Be Inserted, F. Favata, G. Micela, S. Sciortino, A. Kaas
We have for the rst time detected X-ray emission associated with a protostellar jet, on the jet emanating from the L1551 IRS5 protostar. The IRS5 protostar is hidden behind a very large absorbing...
Astron. Nachr./AN 32X (200X) X, XXX--XXX (2007)
The Stellar Content, G. Micela, F. Favata, E. Feigelson, S. Sciortino
Introduction We present our ongoing work on the stellar content of Chandra Deep Field North survey based on the analysis of the 1 Msec data (Brandt et al. 2001) in the 0.5-2.0 keV band. The optical...
E. Flaccomio, F. Damiani, G. Micela, S. Sciortino, F. R. Harnden, S. S. Murray, ...
In this rst of two companion papers on the Orion Nebula Cluster (ONC), we present our analysis of a 63 Ksec Chandra HRC-I observation that yielded 742 X-ray detections within the 30 eld of view. To...
Young Stars Near Earth: Progress and Prospects (2007)
Asp Conference Series, Ray Jayawardhana, Thomas Greene, S. Sciortino, F. Damiani, F. Favata, ...
We present results of our ongoing study of the low-mass members of Upper Sco-Cen based on deep BVRI photometry and XMMNewton EPIC observations purposely obtained as part of the GTO program. Analyzing...
Pillitteri Micela Sciortino, I. Pillitteri, G. Micela, S. Sciortino, F. Favata
We present X-ray Luminosity Distributions (XLDs) of late-type members (dF, dG, dK, dM) of the Blanco 1 cluster, based on ROSAT-HRI data and new astrometric-photometric membership obtained from the...
Astronomy Astrophysics manuscript no. H4001 February 17, 2003 (2007)
Doi Will Be, E. Flaccomio, G. Micela, S. Sciortino
We investigate the evolution of X-ray stellar activity from the age of the youngest known star forming regions (SFR), . 1Myr, to about 100 Myr, i.e. the zero age main sequence (ZAMS) for a 1M star....
Astronomy Astrophysics manuscript no. (2007)
Will Be Inserted, L. Prisinzano, G. Micela, S. Sciortino, F. Favata
We present UBVRI photometry of the open cluster NGC 2422 (age 10 yr) down to a limiting magnitude V ' 19. These data are used to derive the Luminosity and Mass Functions and to study the cluster...
Stellar Coronae in the Chandra and XMM-Newton Era (2007)
Asp Conference Series, J. Drake, S. Sciortino, F. Damiani, F. Favata, F. Favata, ...
As part of our long-term eort to characterize the low-mass stellar population of the Upper Sco-Cen association based on deep Xray surveys and follow-up optical observations we present results from a...
Astronomy Astrophysics manuscript no. (2007)
Will Be Inserted, G. Micela, A. Marino
We analyze the time variations of the solar X-ray luminosity observed with Yohkoh/SXT with the aim to compare the X-ray variability of the Sun with that of the other solar-like main sequence stars as...
Bocchino Damiani Micela, F. Bocchino, F. Damiani, G. Micela, S. Sciortino, F. Favata
We present the results of a ROSAT study of NGC 2422, a southern open cluster at a distance of about 470 pc, with an age close to the Pleiades. Source detection was performed on two observations, a...
Accretion and Outflow-Related X-Rays in T Tauri Stars (2007)
Guedel, M., Briggs, K., Arzner, K., Audard, M., Bouvier, J., Dougados, C., ...
We report on accretion- and outflow-related X-rays from T Tauri stars, based on results from the "XMM-Newton Extended Survey of the Taurus Molecular Cloud." X-rays potentially form in shocks of...
Penz, T., Micela, G., Lammer, H.
Aims: We investigate the influence of high-energy stellar radiation at close-in orbits on atmospheric mass loss during stellar evolution of a G-type star. Methods: High-energy stellar luminosity...
Giardino, G., Favata, F., Pillitteri, I., Flaccomio, E., Micela, G., Sciortino, S.
AIMS. We study the variability of the Fe 6.4 KeV emission line from the Class I young stellar object Elias 29 in the Rho-Oph cloud. METHODS. We analysed the data from Elias 29 collected by XMM during...
X-ray flaring from the young stars in CygnusOB2 (2007)
Colombo, J. F. Albacete, Caramazza, M., Flaccomio, E., Micela, G., Sciortino, S.
Aims: We characterize individual and ensemble properties of X-ray flares from stars in the CygOB2 and ONC star-forming regions. Method: We analyzed X-ray lightcurves of 1003 CygOB2 sources observed...
Coronal abundances of X-ray bright pre-main sequence stars in the Taurus Molecular Cloud (2007)
Scelsi, L., Maggio, A., Micela, G., Briggs, K., Guedel, M.
We studied the thermal properties and chemical composition of the X-ray emitting plasma of a sample of bright members of the Taurus Molecular Cloud to investigate possible differences among classical...
The correlation between soft and hard X-rays component in flares: from the Sun to the stars (2007)
Isola, C., Favata, F., Micela, G., Hudson, H. S.
In this work we study the correlation between the soft (1.6--12.4 keV, mostly thermal) and the hard (20--40 and 60--80 keV, mostly non-thermal) X-ray emission in solar flares up to the most energetic...
Crespo-Chacón, I., Micela, G., Reale, F., Caramazza, M., López-Santiago, J., Pillitteri, I.
Context: Weak flares are supposed to be an important heating agent of the outer layers of stellar atmospheres. However, due to instrumental limitations, only large X-ray flares have been studied in...
X-ray detection of the substellar twin 2MASS J11011926-7732383 AB (2007)
2MASS J11011926-7732383 AB (hereafter 2M1101AB), located in the Cha I star forming region, is a rare wide-separation brown dwarf binary. XMM-Newton and Chandra observations of 2M1101AB have allowed...
X-ray Flares in Orion Low Mass Stars (2007)
Caramazza, M., Flaccomio, E., Micela, G., Reale, F., Wolk, S. J., Feigelson, E. D.
Context. X-ray flares are common phenomena in pre-main sequence stars. Their analysis gives insights into the physics at work in young stellar coronae. The Orion Nebula Cluster offers a unique...
Coronal Abundances in Orion Nebula Cluster Stars (2007)
Maggio, A., Flaccomio, E., Favata, F., Micela, G., Sciortino, S., Feigelson, E. D., ...
Following the Chandra Orion Ultradeep Project (COUP) observation, we have studied the chemical composition of the hot plasma in a sample of 146 X-ray bright pre-main sequence stars in the Orion...
Sanz-Forcada, J., Favata, F., Micela, G.
The observation of eclipses during X-rays flares taking place in active cool stars binaries allows us to calculate the position and size of the flares. This information cannot be derived by analyzing...
Lammer, Helmut, Penz, T., Wuchterl, G., Lichtenegger, H. I. M., Khodachenko, M. L., Kulikov, Yu. N., ...
The orbital distance at which close-in exoplanets maintain their initial mass is investigated by modelling the maximum expected thermal and nonthermal mass loss rates over several Gyr. Depending on...
The X-ray activity-rotation relation of T Tauri stars in Taurus-Auriga (2007)
Briggs, K. R., Guedel, M., Telleschi, A., Preibisch, Th., Stelzer, B., Bouvier, J., ...
The Taurus-Auriga star-forming complex hosts the only population of T Tauri stars in which an anticorrelation of X-ray activity and rotation period has been observed. We have used XMM-Newton's...
Spectral and temporal classification of x-ray sources in young stellar clusters (2007)
Hojnacki, Susan, Micela, G., Flaccomio, E., Kastner, Joel
Luminous, highly variable X-ray emission is one of the defining characteristics of low-mass, pre-main sequence (PMS) stars. A very wide range of temporal behavior has been observed in Chandra and...
Spectral properties of X-ray bright variable sources in the Taurus Molecular Cloud (2006)
Franciosini, E., Pillitteri, I., Stelzer, B., Micela, G., Briggs, K. R., Scelsi, L., ...
We analyze 19 bright variable X-ray sources detected in the XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST), in order to characterize the variations with time of their coronal...
Giardino, G., Favata, F., Micela, G., Sciortino, S., Winston, E.
AIMS: To study the properties of X-ray emissions from young stellar objects (YSOs), through their evolution from Class I to Class III and determine whether Class 0 protostars emit in X-rays. METHODS:...
VLT/Flames observations of the star forming region NGC 6530 (2006)
Prisinzano, L., Damiani, F., Micela, G., Pillitteri, I.
Mechanisms regulating the evolution of pre-main sequence stars can be understood by studying stellar properties such as rotation, disk accretion, internal mixing and binarity. To investigate such...
Simultaneous optical and X-ray observations of a giant flare on the ultracool dwarf LP412-31 (2006)
Stelzer, B., Micela, G., Liefke, C.
Cool stars are known to produce flares probably as a result of magnetic reconnection in their outer atmospheres. We present simultaneous XMM-Newton optical V band and X-ray observations of the M8...
Guarcello, M. G., Prisinzano, L., Micela, G., Damiani, F., Peres, G., Sciortino, S.
Context: the observation of young stars with circumstellar disks suggests that the disks are dissipated, starting from the inner region, by the radiation of the central star and eventually by the...
Unveiling the Cygnus OB2 stellar population with Chandra (2006)
Colombo, J. F. Albacete, Flaccomio, E., Micela, G., Damiani, F., Sciortino, S.
The aim of this work is to identify the so far unknown low mass stellar population of the ~2Myr old Cygnus OB2 region, and to investigate the X-ray and near-IR stellar properties of its members. We...
The stellar content of the XMM-Newton Bright Serendipitous Survey (2006)
Lopez-Santiago, J., Micela, G., Sciortino, S., Favata, F., Caccianiga, A., Della Ceca, R., ...
Context: The comparison of observed counts in a given sky direction with predictions by Galactic models yields constraints to the spatial distribution and the stellar birthrate of young stellar...
The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST) (2006)
Guedel, M., Briggs, K. R., Arzner, K., Audard, M., Bouvier, J., Feigelson, E. D., ...
(abridged:) The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST) surveys the most populated ~5 square degrees of the Taurus star formation region, using the XMM-Newton X-ray...
Stelzer, B., Flaccomio, E., Briggs, K., Micela, G., Scelsi, L., Audard, M., ...
This work is part of a systematic X-ray survey of the Taurus star forming complex with XMM-Newton. We study the time series of all X-ray sources associated with Taurus members, to statistically...
XMM-Newton survey of two Upper Scorpius regions (2006)
Argiroffi, C., Favata, F., Flaccomio, E., Maggio, A., Micela, G., Peres, G., ...
We study X-ray emission from young stars by analyzing deep XMM-Newton observations of two regions of the Upper Scorpius association, having an age of 5 Myr. Based on near infrared and optical...
On the origin of the X-ray emission from Herbig Ae/Be stars (2006)
Stelzer, B., Micela, G., Hamaguchi, K.
We performed a systematic search for Chandra archival observations of Herbig Ae/Be stars. These stars are fully radiative and not expected to support dynamo action analogous to their convective...
ACIS-I observations of NGC2264. Membership and X-ray properties of PMS stars (2006)
Flaccomio, E., Micela, G., Sciortino, S.
We analyze a deep, 100 ksec long, Chandra ACIS observation of NGC2264. We detect 420 sources, 85% of which are associated with known optical and NIR counterparts. More than 90% of these counterparts...
Giardino, G., Favata, F., Silva, B., Micela, G., Reale, F., Sciortino, S.
We present the results of a five-day monitoring campaign with XMM-Newton of six X-ray bright young stellar objects (YSOs) in the star-forming complex L1551 in Taurus. All stars present significant...
The discovery of an expanding X-ray source in the HH 154 protostellar jet (2006)
Favata, F., Bonito, R., Micela, G., Fridlund, M., Orlando, S., Sciortino, S., ...
We have performed, in October 2005, a deep Chandra X-ray observation of HH 154. Comparison with the previous (2001) Chandra observation allows to detect proper motion down to the level predicted by...
Chandra X-Ray Observations of Young Clusters. III. NGC 2264 and the Orion Flanking Fields (2006)
Rebull, L. M., Stauffer, J. R., Ramirez, S. V., Flaccomio, E., Sciortino, S., Micela, G., ...
Chandra observations of solar-like pre-main sequence (PMS) stars in the Orion Flanking Fields (age ~1 Myr) and NGC 2264 (~3 Myr) are compared with the results of the COUP survey of similar objects in...
Stelzer, B., Huelamo, N., Micela, G., Hubrig, S.
There is no straightforward explanation for intrinsic X-ray emission from intermediate-mass main-sequence stars. Therefore the observed emission is often interpreted in terms of (hypothesized)...
Deep X-ray survey of the young open cluster NGC 2516 with XMM-Newton (2006)
Pillitteri, I., Micela, G., Damiani, F., Sciortino, S.
We report on a deep X-ray survey of the young (~ 140 Myr), rich open cluster NGC 2516 obtained with the EPIC camera on board the XMM-Newton satellite. By combining data from six observations, a high...
Lammer, Helmut, Penz, T., Wuchterl, G., L. Khodachenko, M., N. Kulikov, Yu., ...
The orbital distance at which close-in exoplanets maintain their initial mass is investigated by modelling the maximum expected thermal and nonthermal mass loss rates over several Gyr. Depending on...
Simbol-X: mission overview (2006)
Ferrando, P., Arnaud, M., Briel, U., Citterio, O., Clédassou, R., Duchon, P., ...
Lammer, Helmut, Penz, T., Wuchterl, G., L. Khodachenko, M., N. Kulikov, Yu., ...
The orbital distance at which close-in exoplanets maintain their initial mass is investigated by modelling the maximum expected thermal and nonthermal mass loss rates over several Gyr. Depending on...
Astronomy Astrophysics manuscript no. example c (2006)
Eso October Correlation, M. G. Guarcello, L. Prisinzano, G. Micela, F. Damiani, G. Peres, ...
Context. The observation of young stars with circumstellar disks suggests that the disks are dissipated, starting from the inner region, by the radiation of the central star and eventually by the...
Astronomy Astrophysics manuscript no. 5011 c (2006)
Eso September The, F. Damiani, G. Micela, S. Sciortino, N. Huélamo, A. Moitinho, ...
Context. We study the stellar population of the very young cluster NGC 2362, using a deep Chandra ACIS-I X-ray observation. This cluster, only 5 Myr old, has already cleared most of its inter- and...
Astronomy Astrophysics manuscript no. aa20054405 c ESO 2006 (2006)
February Testing The, B. Stelzer, N. Huélamo, G. Micela, S. Hubrig
Context. The X-ray emission from B-type main-sequence stars is a longstanding mystery in stellar coronal research. Since there is no theory at hand that explains intrinsic X-ray emission from...
Astronomy Astrophysics manuscript no. 6536 c (2006)
Eso November Spectral, E. Franciosini, I. Pillitteri, B. Stelzer, G. Micela, K. R. Briggs, ...
Aims. We analyze 19 bright variable X-ray sources detected in the XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST), in order to characterize the variations with time of their coronal...
Astronomy Astrophysics manuscript no. 4003 c (2006)
Eso January Deep, I. Pillitteri, G. Micela, F. Damiani, S. Sciortino
Aims. We report a deep X-ray survey of the young ( 140 Myr), rich open cluster NGC 2516 obtained with the EPIC camera on board the XMM-Newton satellite.
Astronomy Astrophysics manuscript no. 5006 c ESO 2006 (2006)
May On The, B. Stelzer, G. Micela, K. Hamaguchi
Context. Herbig Ae/Be stars are fully radiative and not expected to support dynamo action analogous to their convective lower-mass counterparts, the T Tauri stars. Alternative X-ray production...
Astronomy Astrophysics manuscript no. aa6043 c (2006)
Eso August Statistical, B. Stelzer, E. Flaccomio, K. Briggs, G. Micela, L. Scelsi, ...
Context. This work is part of a systematic X-ray survey of the Taurus star forming complex with XMM-Newton.
Astronomy Astrophysics manuscript no. aa6488 c (2006)
Eso October Simultaneous, B. Stelzer, G. Micela, C. Liefke
Cool stars are known to produce flares probably as a result of magnetic reconnection in their outer atmospheres. We present simultaneous XMM-Newton optical V band and X-ray observations of the M8...
Astronomy Astrophysics manuscript no. upsco c (2006)
Eso Th July, C. Argiroffi, F. Favata, E. Flaccomio, A. Maggio, G. Micela, ...
Aims. We study X-ray emission from young stars by analyzing deep XMM-Newton observations of two regions of the Upper Scorpius association, having an age of 5 Myr.
Astronomy Astrophysics manuscript no. n6530 c ESO 2006 (2006)
October Vlt Flames, L. Prisinzano, F. Damiani, G. Micela, I. Pillitteri
Context. Mechanisms regulating the evolution of pre-main sequence stars can be understood by studying stellar properties such as rotation, disk accretion, internal mixing and binarity. To investigate...
Stelzer, B., Micela, G., Flaccomio, E., Neuhaeuser, R., Jayawardhana, R., ...
Three brown dwarfs in different evolutionary stages have been observed with the Chandra X-ray Observatory. Combining the new observations with previous studies presented in the literature yields a...
A compact flare eclipsed in the corona of SV Cam (2005)
Sanz-Forcada, J., Favata, F., Micela, G.
The eclipsing active binary SV Cam (G0V/K6V, P_0.593071 d) was observed with XMM-Newton during two campaigns in 2001 and 2003. No eclipses in the quiescent emission are clearly identified, but a...
Wolk, S. J., Flaccomio, E., Micela, G., Favata, F., Glassgold, A. E., Shang, H., ...
In January 2003, the Chandra Orion Ultradeep Project (COUP) detected about 1400 young stars during a 13.2 day observation of the Orion Nebula Cluster (ONC). This paper studies a well-defined sample...
Rotational modulation of X-ray emission in Orion Nebula young stars (2005)
Flaccomio, E., Micela, G., Sciortino, S., Feigelson, E. D., Herbst, W., Favata, F., ...
We investigate the spatial distribution of X-ray emitting plasma in a sample of young Orion Nebula Cluster stars by modulation of their X-ray light-curves due to stellar rotation. The study, part of...
Bright X-ray flares in Orion young stars from COUP: evidence for star-disk magnetic fields? (2005)
Favata, F., Flaccomio, E., Reale, F., Micela, G., Sciortino, S., Shang, H., ...
We have analyzed a number of intense X-ray flares observed in the Chandra Orion Ultradeep Project (COUP), a 13 days observation of the Orion Nebula Cluster (ONC). Analysis of the flare decay allows...
X-ray emission from early-type stars in the Orion Nebula Cluster (2005)
Stelzer, B., Flaccomio, E., Montmerle, T., Micela, G., Sciortino, S., Favata, F., ...
The X-ray properties of twenty ~1 Myr old O, B, and A stars of the Orion Trapezium are examined with data from the Chandra Orion Ultradeep Project (COUP). On the basis of simple theories for X-ray...
Membership of the Orion Nebula Population from the Chandra Orion Ultradeep Project (2005)
Getman, K. V., Feigelson, E. D., Grosso, N., McCaughrean, M. J., Micela, G., Broos, P., ...
The Chandra Orion Ultradeep project (COUP) observation described in a companion paper by Getman et al. provides an exceptionally deep X-ray survey of the Orion Nebula Cluster and associated embedded...
COUP census of X-ray stars in BN-KL and OMC-1S (2005)
Grosso, N., Feigelson, E. D., Getman, K. V., Townsley, L., Broos, P., Flaccomio, E., ...
We present a study of the X-ray sources detected in the vicinity of two density peaks in the Orion Molecular Cloud 1 (OMC-1) behind the Orion Nebula Cluster (ONC), as seen in the exceptionally deep...
Affer, L, Micela, G, Morel, Thierry; U0048260, Sanz-Forcada, J, Favata, F
High resolution, high - S/N- ratio optical spectra have been obtained for a sample of 6 K-type dwarf and subgiant stars, and have been analysed with three different LTE methods in order to derive...
Chandra Orion Ultradeep Project : Observations and source lists (2005)
Getman, K. V., Flaccomio, E., Broos, P. S., Grosso, N., Tsujimoto, M., Townsley, L., ...
The origin of T tauri X-ray emission : New insights from the Chandra Orion Ultradeep Project (2005)
Preibisch, T., Kim, Y. C., Favata, F., Feigelson, E. D., Flaccomio, E., Getman, K., ...
X-ray emission from young brown dwarfs in the Orion Nebula Cluster (2005)
Preibisch, T., McCaughrean, M. J., Grosso, N., Feigelson, E. D., Flaccomio, E., Getman, K., ...
X-ray emission from early-type stars in the Orion Nebula Cluster (2005)
Stelzer, B., Flaccomio, E., Montmerle, T., Micela, G., Sciortino, S., Favata, F., ...
The Life of Stars and their Planets (2005)
Catala, C., Aerts, C., Aigrain, S., Antonello, E., Appourchaux, T., Auvergne, M., ...
We lack a reliable scenario for the formation and evollution of stars and their planetary systems, involving key factors such as magnetic fields and turbulence. We present the case for a mission...
Iron Fluorescent Line Emission from Young Stellar Objects in the Orion Nebula (2004)
Tsujimoto, M., Feigelson, E. D., Grosso, N., Micela, G., Tsuboi, Y., Favata, F., ...
We present the result of a systematic search for the iron Kalpha fluorescent line at 6.4 keV among 1616 X-ray sources detected by ultra-deep Chandra observations of the Orion Nebula Cluster and the...
Favata, F., Micela, G., Silva, B., Sciortino, S., Tsujimoto, M.
We report the results of a search for 6.4 keV Fe fluorescent emission in Young Stellar Objects (YSOs) with measured accretion luminosities in the rho Oph cloud, using all existing chandra and...
Morel, Thierry; U0048260, Micela, G, Favata, F, Katz, D
We report the determination from high-resolution spectra of the atmospheric parameters and abundances of 13 chemical species ( among which lithium) in 8 single-lined active binaries. These data are...
X-ray spectral and timing characteristics of the stars in the young open cluster IC 2391 (2004)
Marino, A., Micela, G., Peres, G., Pillitteri, I., Sciortino, S.
We present X-ray spectral and timing analysis of members of the young open cluster IC 2391 observed with the XMM-Newton observatory. We detected 99 X-ray sources by analysing the summed data obtained...
Chandra Orion Ultradeep Project: Observations and Source Lists (2004)
Getman, K. V., Flaccomio, E., Broos, P. S., Grosso, N., Tsujimoto, M., Townsley, L., ...
We present a description of the data reduction methods and the derived catalog of more than 1600 X-ray point sources from the exceptionally deep January 2003 Chandra X-ray Observatory observation of...
The Star Formation Region NGC 6530: distance, ages and Initial Mass Function (2004)
Prisinzano, L., Damiani, F., Micela, G., Sciortino, S.
We present astrometry and $BVI$ photometry, down to $V\simeq22$, of the very young open cluster NGC6530, obtained from observations taken with the Wide Field Imager camera at the MPG/ESO 2.2 m...
Multiwavelength study of X-ray emitting A- and B-stars testing the companion hypothesis (2004)
Stelzer, B., Huelamo, N., Hubrig, S., Micela, G., Zinnecker, H., Guenther, E.
We report on the first results of a multi-wavelength approach to test the hypothesis that the X-ray emission from intermediate-mass stars is generated by late-type magnetically active companions. Our...
On the determination of oxygen abundances in chromospherically active stars (2004)
Morel, Thierry; U0048260, Micela, G
We discuss oxygen abundances derived from [O I] lambda6300 and the O I triplet in stars spanning a wide range in chromospheric activity level, and show that these two indicators yield increasingly...
Giardino, G., Favata, F., Micela, G.
We present Chandra observations of the massive star-forming region S106, a prominent HII region in Cygnus, associated with an extended molecular cloud and a young cluster. The nebula is excited by a...
Morel, T., Micela, G., Favata, F., Katz, D.
We report the determination from high-resolution spectra of the atmospheric parameters and abundances of 13 chemical species (among which lithium) in 8 single-lined active binaries. These data are...
X-ray spectroscopy of the unsteady quiescent corona of AD Leo with Chandra (2004)
Maggio, A., Drake, J. J., Kashyap, V., Harnden, F. R., Micela, G., ...
We present the analysis and interpretation of an observation of the flare star AD Leo (dM3e) with Chandra/LETG. The high resolution X-ray spectrum allowed us to infer the plasma emission measure...
On the determination of oxygen abundances in chromospherically active stars (2004)
We discuss oxygen abundances derived from [O I] 6300 and the O I triplet in stars spanning a wide range in chromospheric activity level, and show that these two indicators yield increasingly...
Feigelson, E. D., Hornschemeier, A. E., Micela, G., Bauer, F. E., Alexander, D. M., Brandt, W. N., ...
The extremely sensitive Chandra Deep Field-North (CDF-N) pencil-beam X-ray survey is used to identify and characterize the X-ray emission from old high-latitude main sequence Galactic stars. Our...
XMM-Newton probes the stellar population in Cha I South (2004)
Stelzer, B., Micela, G., Neuhaeuser, R.
We report on a 30ksec XMM-Newton observation of the central region of the Cha I star forming cloud. Virtually all known T Tauri star members and most of the very-low mass objects including two...
Pillitteri, I., Micela, G., Sciortino, S., Damiani, F., Harnden Jr, F. R.
We present an X-ray study of the high metallicity young open cluster Blanco 1 based on XMM--Newton data. X-ray spectroscopy of cluster members is presented for the first time as well as new X-ray...
Favata, F., Micela, G., Baliunas, S. L.
We present the initial results from our XMM program aimed at searching for X-ray activity cycles in solar-type stars. HD 81809 is a G2-type star (somewhat more evolved than the Sun, and with a less...
Parameter properties and stellar population of the old open cluster NGC 3960 (2004)
Prisinzano, L., Micela, G., Sciortino, S., Favata, F.
We present a $BVI$ photometric and astrometric catalogue of the open cluster NGC 3960, down to limiting magnitude $V\sim22$, obtained from observations taken with the Wide Field Imager camera at the...
Hojnacki, Susan, Kastner, Joel, Micela, G., Feigelson, E. D., Grosso, N.
We are developing an automated classification technique to group X-ray sources detected in CCD imaging into clusters based on X-ray spectral attributes. The algorithm is non-parametric and uses...
Parameter properties and stellar population of the old open cluster NGC 3960 (2004)
L. Prisinzano, G. Micela, S. Sciortino, F. Favata
We present a BVI photometric and astrometric catalogue of the open cluster NGC 3960, down to limiting magnitude V 22, obtained from observations taken with the Wide Field Imager camera at the MPG/ESO...
Coronal versus photospheric abundances of stars with different activity levels (2004)
J. Sanz-Forcada, F. Favata, G. Micela
We report a detailed analysis of the coronal abundance of 4 stars with varying levels of activity and with accurately known photospheric abundances. The coronal abundance is determined here using a...
Astronomy Astrophysics manuscript no. (2004)
Will Be Inserted, L. Affer, G. Micela, T. Morel, J. Sanz-forcada, F. Favata
High resolution, high-S/N-ratio optical spectra have been obtained for a sample of 6 K-type dwarf and subgiant stars, and have been analysed with three di#erent LTE methods in order to derive...
Astronomy Astrophysics manuscript no. gb041 March 5, 2004 (2004)
Doi Will Be, F. Favata, G. Micela, S. L. Baliunas, M. Güdel, ...
We present the initial results from our XMM-Newton program aimed at searching for X-ray activity cycles in solar-type stars. HD 81809 is a G2-type star (somewhat more evolved than the Sun, and with a...
Morel, Thierry; U0048260, Micela, G, Favata, F, Katz, D, Pillitteri, I
Photospheric parameters and abundances are presented for a sample of single-lined chromospherically active binaries from a differential LTE analysis of high-resolution spectra. Abundances have been...
Coronal versus photospheric abundances of stars with different activity levels (2003)
Sanz-Forcada, J., Favata, F., Micela, G.
We report a detailed analysis of the coronal abundance of 4 stars with varying levels of activity and with accurately known photospheric abundances. The coronal abundance is determined here using a...
A large X-ray flare from the Herbig Ae star V892 Tau (2003)
Giardino, G., Favata, F., Micela, G., Reale, F.
We report the XMM-Newton observation of a large X-ray flare from the Herbig Ae star V892 Tau. The apparent low mass companion of V892 Tau, V892 Tau NE, is unresolved by XMM-Newton. Nevertheless there...
Morel, T., Micela, G., Favata, F., Katz, D., Pillitteri, I.
Photospheric parameters and abundances are presented for a sample of single-lined chromospherically active binaries from a differential LTE analysis of high-resolution spectra. Abundances have been...
X-ray rotational modulation of a supersaturated star in IC 2391 (2003)
Marino, A., Micela, G., Peres, G., Sciortino, S.
We present evidence of X-ray rotational modulation on VXR45, a young fast rotator star, member of IC 2391. It is a dG9 spectral type star whose rotational period and X-ray luminosity make it a...
Late B-type stars and their candidate companions resolved with Chandra (2003)
Stelzer, B., Huelamo, N., Hubrig, S., Zinnecker, H., Micela, G., ...
We present the first results from a series of Chandra observations carried out with the aim to examine the origin of X-ray emission in main-sequence late B-type stars. We use high spatial resolution...
Luminosity and Mass Function of the Galactic open cluster NGC 2422 (2003)
Prisinzano, L., Micela, G., Sciortino, S., Favata, F.
We present UBVRI photometry of the open cluster NGC 2422 (age $\sim 10^8$ yr) down to a limiting magnitude $V\simeq19$. These data are used to derive the Luminosity and Mass Functions and to study...
Favata, F., Giardino, G., Micela, G., Sciortino, S., Damiani, F.
We present a study of the X-ray sources present in the nearby L1551 star forming region, based on a deep XMM observation complemented with Chandra data for the brightest sources. All the known...
Flaccomio, E., Micela, G., Sciortino, S.
We investigate the evolution of X-ray stellar activity from the age of the youngest known star forming regions (SFR), < 1Myr, to about 100 Myr, i.e. the zero age main sequence (ZAMS) for a ~ 1M_sun...
Chandra X-Ray Observations of the Young Open Cluster NGC 2516 (2003)
Damiani Flaccomio Micela, F. Damiani, E. Flaccomio, G. Micela, S. Sciortino, F. R. Harnden, ...
We present a comprehensive study of the Chandra X-ray observations of the young open cluster NGC 2516. We have analyzed 8 individual Chandra observations. We have combined the data to achieve the...
Katz, D., Favata, F., Aigrain, S., Micela, G.
The high-resolution optical spectra of the two X-ray active binaries RS CVn stars HD 113816 (IS Vir) and HD 119285 (V851 Cen) are analysed and their Na, Mg, Al, Si, Ca, Sc, Ti, Co and Ni contents...
Observational clues for a role of circumstellar accretion in PMS X-ray activity (2002)
Flaccomio, E., Micela, G., Sciortino, S.
We revisit the published analyses of ROSAT X-ray observations of the star forming regions NGC 2264 and Chamaeleon I (~3 and ~5 Myr old respectively) in the light of newly published optical data. At...
Flaccomio, E., Damiani, F., Micela, G., Sciortino, S., Harnden Jr., F. R., Murray, S. S., ...
In this first of two companion papers on the Orion Nebula Cluster (ONC), we present our analysis of a 63 Ksec Chandra HRC-I observation that yielded 742 X-ray detections within the 30'x30' field of...
Flaccomio, E., Damiani, F., Micela, G., Sciortino, S., Harnden Jr., F. R., Murray, S. S., ...
Using the results of our first paper on the Chandra HRC observation of the Orion Nebula Cluster (ONC), here we explore the relation between the coronal activity of its 1-Myr-old pre-main sequence...
The EUVE point of view of AD Leo (2002)
All the Extreme Ultraviolet Explorer (EUVE) observations of AD Leo, totalling 1.1 Ms of exposure time, have been employed to analyze the corona of this single M dwarf. The light curves show a well...
Astronomy Astrophysics manuscript no. aa2680 (2002)
Doi Will Be, N. Pizzolato, A. Maggio, G. Micela, S. Sciortino, P. Ventura
We present the results of a new study on the relationship between coronal X-ray emission and stellar rotation in late-type main-sequence stars. We have selected a sample of 259 dwarfs in the B V...
The discovery of X-ray emission from the protostellar jet L1551 IRS5 (HH 154) (2001)
Favata, F., Fridlund, C. V. M., Micela, G., Sciortino, S., Kaas, A. A.
We have for the first time detected X-ray emission associated with a protostellar jet, on the jet emanating from the L1551 IRS5 protostar. The IRS5 protostar is hidden behind a very large absorbing...
Discovery of X-ray emission from the proto-stellar jet L1551 IRS5 (HH 154) (2001)
Favata, Fabio, Fridlund, C. V. M., Micela, G., Sciortino, S., Kaas, A. A.
We have for the first time detected X-ray emission associated with a proto-stellar jet, on the jet emanating from L1551 IRS5. The IRS5 proto-star is hidden beyond a very large absorbing column...
Coronal structure geometries on pre-main sequence stars (2001)
Favata, F., Micela, G., Reale, F.
We have re-analyzed using a hydrodynamic model large flaring events on three different categories of pre-main sequence (PMS) stars: the young stellar object (YSO) YLW 15, the classical T Tauri star...
A ROSAT medium-sensitivity Galactic plane survey at 180 degrees (2001)
Morley, J.E., Briggs, K.R., Pye, J.P., Favata, F., Micela, G., Sciortino, S.
XMM-Newton survey of the low-metallicity open cluster NGC 2516 (2000)
Sciortino, S., Micela, G., Damiani, F., Flaccomio, E., Briggs, K., Denby, M., ...
We present the first results of an XMM-Newton EPIC survey of NGC 2516, a southern low-metallicity open cluster with an age close to the Pleiades. The attained limiting sensitivity is of ~ 2.4 10^-15...
Will Be Inserted, F. Favata, G. Micela, F. Reale, S. Sciortino
We present a systematic analysis of the four known large X-ray flares detected to date on the eclipsing binary system Algol, using an approach based on hydrodynamic simulations of decaying flaring...
The corona of the dMe flare star AD Leo (1999)
Favata, Fabio, Micela, G., Reale, F.
We have studied the X-ray emission (both the quiescent component and the flares) of the dM3e star AD Leo, analyzing the Einstein IPC, ROSAT PSPC and ASCA SIS observations. Using a consistent method...
An extreme X-ray flare observed on EV Lac by ASCA in July 1998 (1999)
Favata, F., Reale, F., Micela, G., Sciortino, S., Maggio, A., Matsumoto, H.
We present a long (150 ks elapsed time) ASCA X-ray observation of the dM3.5e star EV Lac, during which an exceptionally intense flaring event (lasting approximately 12 ks) was observed: at the...
On the widespread Weak-Line T-Tauri population detected in the ROSAT All-Sky Survey (1997)
Favata, F., Micela, G., Sciortino, S.
We discuss the apparent widespread presence of Weak-Line T-Tauri stars (WTTS) among stellar coronal sources detected in the ROSAT All-Sky Survey (RASS), and their relative number with respect to...
A SAX/LECS X-ray observation of the active binary Capella (1997)
Favata, F., Mewe, R., Brickhouse, N. S., Pallavicini, R., Micela, G., Dupree, A. K.
We present a SAX/LECS X-ray observation of the active binary Capella, the first coronal source observed in the SAX Guest Investigator program. The analysis of this observation, performed using the...
Will Be Inserted, F. Favata, G. Micela, S. Sciortino
We discuss the apparent widespread presence of Weak-Line T-Tauri stars (WTTS) among stellar coronal sources detected in the ROSAT All-Sky Survey (RASS), and their relative number with respect to...
Will Be Inserted, S. Sciortino, F. Damiani, F. Favata, G. Micela
We have searched for low-mass pre-main-sequence stars in the nearby Upper Sco-Cen star-forming region using ROSAT observations analyzed with an innovative source detection method based on wavelet...
Favata Sciortino, G. Micela, F. Favata, S. Sciortino
We present the parallaxes, measured by Hipparcos, for a sample of X-ray selected stars. The stars belong to the stellar sample of the Einstein Extended Medium Sensitivity Survey. They are all at...
THE EVOLUTIONARY STATUS OF HIGH-LITHIUM, HIGH-ACTIVITY COOL DWARFS F. Favata
Micela Sciortino Antona, F. Favata, G. Micela, S. Sciortino
We have used the newly available Hipparcos precise parallaxes to study the evolutionary status of a number of high-lithium, high-activity late-type dwarfs found in X-ray based surveys, the Einstein...
Royal Greenwich Observatory, Madingley Road, Cambridge, CB3 0EZ, UK
. We have performed a moderately deep soft X-ray survey of the Galactic Plane using pointed observations with the ROSAT Position Sensitive Proportional Counter. The survey is more than an order of...
X-ray properties of protostars in the Orion Nebula
L. Prisinzano, G. Micela, E. Flaccomio, J. R. Stauffer, T. Megeath, L. Rebull, ...
The origin and evolution of the X-ray emission in very young stellar objects (YSOs) are not yet well understood because it is very hard to observe YSOs in the protostellar phase. We study the X-ray...