Unveiling the nature of six HMXBs through IR spectroscopy (2008)
Nespoli, E., Fabregat, J., Mennickent, R. E.
The International Gamma-Ray Astrophyiscs Laboratory (INTEGRAL) is discovering a large number of new hard X-ray sources, many of them being HMXBs. The identification and spectral characterization of...
The eclipsing LMC star OGLE05155332--6925581: a clue for Double Periodic Variables (2008)
Mennickent, R. E., Kolaczkowski, Z., Michalska, G., Pietrzy'nski, G., Gallardo, R., Cidale, L., ...
We investigate the nature of OGLE05155332-6925581, one of the brightest members of the enigmatic group of Double Periodic Variables (DPVs) recently found in the Magellanic Clouds. The modeling of...
Two Be stars in the Small Magellanic Cloud with B[e]-like properties (2008)
Mennickent, R. E., Smith, M., Kolaczkowski, Z.
We present an analysis of UVES and MIKE (ground based) high resolution and Far Ultraviolet Spectroscopic Explorer spectra of two novel and photometrically variable bright blue stars in the SMC;...
Variability in the cycle length of the supersoft source RX J0513.9-6951 (2008)
Burwitz, V., Reinsch, K., Greiner, J., Meyer-Hofmeister, E., Meyer, F., Walter, F. M., ...
The supersoft X-ray binary RX J0513.9-6951 shows cyclic changes between optical-low / X-ray-on states and optical-high / X-ray-off states. It is supposed to be accreting close to the...
Variability in the cycle length of the supersoft source RX J0513.9-6951 (2008)
Burwitz, V., Reinsch, K., Greiner, J., Meyer-Hofmeister, E., Meyer, F., Walter, F. M., ...
Variability in the cycle length of the supersoft source RX J0513.9-6951 (2008)
Burwitz, V., Reinsch, K., Greiner, J., Meyer-Hofmeister, E., Meyer, F., Walter, F. M., ...
Possible optical detection of a fast, nearby radio pulsar PSR B1133+16 (2007)
Zharikov, S. V., Shibanov, Yu. A., Mennickent, R. E., Komarova, V. N.
Aims: We performed deep optical observations of the field of an old, fast-moving radio pulsar PSR B1133+16 in an attempt to detect its optical counterpart and a bow shock nebula. Methods: The...
The remarkable properties of the symbiotic star AE Circinus (2007)
Mennickent, R. E., Greiner, J., Arenas, J., Tovmassian, G., Mason, E., Tappert, C., ...
We present new optical spectroscopy and photometry, 2MASS infrared observations and 24 years of combined AAVSO and AFOEV photometry of the symbiotic star candidate \ae. The long-term light curve is...
A Catalogue of Be Stars in the Direction of the Galactic Bulge (2007)
Sabogal, B. E., Mennickent, R. E., Pietrzyński, G., García, J. A., Gieren, W., Kolaczkowski, Z., ...
Detailed studies of Be stars in environments with different metallicities like the Magellanic Clouds or the Galactic bulge are necessary to understand the formation and evolution mechanisms of the...
The pre-cataclysmic variable, LTT560 (2007)
Tappert, C., Gaensicke, B. T., Schmidtobreick, L., Aungwerojwit, A., Mennickent, R. E., Koester, D.
System parameters of the object LTT560 are determined in order to clarify its nature and evolutionary status. We apply time-series photometry to reveal orbital modulations of the light curve,...
K-band spectroscopy of pre-cataclysmic variables (2007)
Tappert, C., Gaensicke, B. T., Schmidtobreick, L., Mennickent, R. E., Navarrete, F. P.
We have taken K-band spectroscopy of a sample of 13 pre-CVs in order to examine them for anomalous chemical abundances. In particular, we study the strength of the 12CO and 13CO absorption bands that...
Spectroscopy of blue and yellow long-period variables in the small magellanic cloud (2006)
R. E. Mennickent, W. Gieren, L. S. Cidale, G. Pietrzynski, B. Sabogal
Spectroscopy of blue and yellow long-period variables in the small magellanic cloud
Optical spectroscopy of the radio pulsar PSR B0656+14 (2006)
Zharikov, S., Mennickent, R. E., Shibanov, Yu., Komarova, V.
We have obtained the spectrum of a middle-aged PSR B0656+14 in the 4300-9000 AA range with the ESO/VLT/FORS2. Preliminary results show that at 4600-7000 AA the spectrum is almost featureless and flat...
The Araucaria Project. Bright Variable Stars in NGC 6822 from a Wide-Field Imaging Survey (2006)
Mennickent, R. E., Gieren, W., Soszynski, I., Pietrzynski, G.
We have performed a search for variable stars in the dwarf irregular galaxy NGC 6822 using wide-field multi-epoch VI photometry down to a limiting magnitude $V$ $\sim$ 22. Apart from the Cepheid...
Spectroscopy of the candidate pre-CV LTT 560 (2006)
Tappert, C., Gaensicke, B. T., Mennickent, R. E., Schmidtobreick, L.
We present preliminary results on spectroscopic data of the candidate pre-cataclysmic variable LTT 560. A fit to the flux-calibrated spectrum reveals the temperature of the white-dwarf primary to be...
Spectroscopy of blue and yellow long-period variables in the small magellanic cloud (2006)
Cidale, L. S., Gieren, W., Mennickent, R. E., Pietrzynski, G., Sabogal, B.
Presentamos espectroscopía de 17 estrellas variables brillantes posibles miembros de la Nube Pequeña de Magallanes. Estas estrellas son variables OGLE cuya periodicidad fotométrica no ha sido...
A Direct Distance to the LMC Cepheid HV 12198 from the Infrared Surface Brightness Technique (2005)
Gieren, W. P., Storm, J., Fouque, P., Mennickent, R. E., Gomez, M.
We report on a first application of the infrared surface brightness technique on a Cepheid in the Large Magellanic Cloud, the variable HV 12198 in the young globular cluster NGC 1866. From this one...
Uemura, M., Mennickent, R. E., Ishioka, R., Imada, A., Kato, T., Nogami, D., ...
We report optical photometric observations of four superoutbursts of the short-period dwarf nova TV Crv. This object experiences two types of superoutbursts; one with a precursor and the other...
Spectroscopic analysis of tremendous--outburst--nova candidates (2004)
Schmidtobreick, L., Tappert, C., Bianchini, A., Mennickent, R. E.
In the course of a long-term project investigating classical novae with large outburst amplitudes, we have performed optical spectroscopy of several old-nova candidates. We here present the spectra...
IR spectroscopy of pre-cataclysmic binaries (2004)
Tappert, C., Gaensicke, B. T., Mennickent, R. E.
We have taken near-infrared (JHK) spectroscopic data of a sample of pre-CVs, in order to examine them for signatures of nuclear evolution. Here we present preliminary results for the three systems...
Bianchini , A., Mennickent , R. E., Schmidtobreick , L., Tappert , C.
Durante un proyecto a largo plazo dedicado a la investigación de novas clásicas con explosiones de grandes amplitudes hemos llevado a cabo fotometría a múltiples longitudes de onda y...
Search for brown-dwarf like secondaries in cataclysmic variables II (2003)
Mennickent, R. E., Diaz, M. P., Tappert, C.
We have examined VTL/ISAAC 1-2.5 $\umu$m spectroscopy of a sample of short orbital period cataclysmic variables which are candidates for harboring substellar companions. We provide descriptions of...
Recovery of the old nova V840 Ophiuchi: A carbon rich system (2003)
Schmidtobreick, L., Tappert, C., Bianchini, A., Mennickent, R. E.
We present optical spectroscopy and multi colour photometry of the old nova V840 Oph. We rediscovered the nova based on its position in the colour--colour diagrams. It stands out as a very blue...
An atlas of line profile studies for SU UMa type cataclysmic variables (2003)
Tappert, C., Mennickent, R. E., Arenas, J., Matsumoto, K., Hanuschik, R. W.
We present H-alpha line-profile analyses for the seven SU UMa type dwarf novae AK Cnc, WX Cet, AQ Eri, VW Hyi, RZ Leo, TU Men, and HS Vir. All data sets are treated in the same manner, applying a...
Double-periodic blue variables in the Magellanic Clouds (2002)
Mennickent, R. E., Pietrzynski, G., Diaz, M., Gieren, W.
We report the discovery, based on an inspection of the OGLE-II database, of a group of blue variables in the Magellanic Clouds showing simultaneously two kinds of photometric variability: a...
Light Curve Analysis of Be Star Candidates in the Small Magellanic Cloud (2002)
Mennickent, R. E., Pietrzynski, G., Gieren, W.
The recent discovery, based on a search of public OGLE data, of Be star candidates in the Small Magellanic Cloud showing spectacular photometric variations (Mennickent et al. 2002), has motivated...
On the orbital period of the cataclysmic variable V592 Herculis (2002)
Mennickent, R. E., Tappert, C., Gallardo, R., Duerbeck, H. W., Augusteijn, T.
We present a spectroscopic study of the long-recurrence-time dwarf nova V592 Herculis based on observations obtained during its August 1998 superoutburst. From the analysis of the radial velocities...
A search for brown-dwarf like secondaries in cataclysmic variables (2002)
Mennickent, R. E., Diaz, M. P.
We present VTL/ISAAC infrared spectroscopy of a sample of short orbital period cataclysmic variables which are candidates for harboring substellar companions. We have detected the KI and NaI...
Mennickent, R. E., Pietrzynski, G., Gieren, W., Szewczyk, O.
Recently the OGLE experiment has provided accurate light curves and colours for about 2 millions stars in the Small Magellanic Cloud. We have examined this database for its content of Be stars,...
On the secondary star of the cataclysmic variable 1RXS J094432.1+035738 (2001)
Mennickent, R. E., Tovmassian, G., Zharikov, S. V., Tappert, C., Greiner, J., Gansicke, B. T., ...
We present V and Rc band photometry and optical near-infrared spectroscopy of the cataclysmic variable 1RXS J094432.1+035738. We detected features of a cool secondary star, which can be modeled with...
High spectral resolution time-resolved optical spectroscopy of V893 Sco (2001)
Mason, E., Skidmore, W., Howell, S. B., Mennickent, R. E.
We present high resolution time-resolved optical spectra of the high inclination short orbital period dwarf nova V893 Sco. We performed spectral analysis through radial velocity measurements, Doppler...
Discovery of a cataclysmic variable with a sub-stellar companion (2001)
Mennickent, R. E., Diaz, M., Skidmore, W., Sterken, C.
We find that the ROSAT source 1RXS J105010.3-140431 is a cataclysmic variable with orbital period of 88.6 minutes and a spectrum closely resembling WZ Sge. In particular, emission lines are flanked...
Identification of the donor in the X-ray binary GRS 1915+105 (2001)
Greiner, J., Cuby, J. G., McCaughrean, M. J., Castro-Tirado, A. J., Mennickent, R. E.
We report on the results of medium-resolution spectroscopy of GRS 1915+105 in the near-infrared H and K band using the 8m VLT at ESO. We clearly identify absorption bandheads from 12CO and 13CO....
On the orbital period of the cataclysmic variable RZ Leonis (2001)
Mennickent, R. E., Tappert, C.
In this research note we present a time-resolved study of the Balmer emission lines of RZ Leo. From the analysis of the radial velocities we find an orbital period of 0.07651(26) d. This is in...
Identification of the donor in GRS 1915+105 (2000)
Greiner, J., McCaughrean, M. J., Cuby, J. G., Castro-Tirado, A. J., Mennickent, R. E.
We report on the results of medium-resolution spectroscopy of GRS 1915+105 in the H and K band using the 8m VLT at ESO. We clearly identify absorption bandheads from CO12 and CO13. Together with...
A Direct Distance to the LMC Cepheid HV 12198 from the Infrared Surface Brightness Technique (2000)
Gieren, W. P., Storm, J., Fouque, P., Mennickent, R. E., Gomez, M.
We report on a first application of the infrared surface brightness technique on a Cepheid in the Large Magellanic Cloud, the variable HV 12198 in the young globular cluster NGC 1866. From this one...
A Direct Distance to the LMC Cepheid HV 12198 from the Infrared Surface Brightness Technique (2000)
Gieren, W. P., Storm, J., Fouque, P., Mennickent, R. E., Gomez, M.
We report on a first application of the infrared surface brightness technique on a Cepheid in the Large Magellanic Cloud, the variable HV 12198 in the young globular cluster NGC 1866. From this one...
A Direct Distance to the LMC Cepheid HV 12198 from the Infrared Surface Brightness Technique (2000)
Gieren, W. P., Storm, J., Fouque, P., Mennickent, R. E., Gomez, M.
We report on a first application of the infrared surface brightness technique on a Cepheid in the Large Magellanic Cloud, the variable HV 12198 in the young globular cluster NGC 1866. From this one...
The dwarf nova RZ Leonis : photometric period, "anti-humps" and normal alpha disk (1999)
Mennickent, R. E., Sterken, C., Gieren, W., Unda, E.
We present results of differential photometry of the dwarf nova RZ Leonis spanning a 11-year baseline. The most striking feature of the light curve is a non-coherent periodic hump of variable...