The physics and modes of star cluster formation: observations (2009)
Stellar clusters are born in cold and dusty molecular clouds and the youngest clusters are embedded to various degrees in dusty dark molecular material. Such embedded clusters can be considered...
A Spitzer Census of Star Formation Activity in the Pipe Nebula (2009)
Forbrich, Jan, Lada, Charles J., Muench, August A., Alves, João, Lombardi, Marco
The Pipe Nebula, a large nearby molecular cloud lacks obvious signposts of star formation in all but one of more than 130 dust extinction cores that have been identified within it. In order to...
Román-Zúñiga, Carlos G., Lada, Charles J., Alves, João F.
We present our analysis of a fully sampled, high resolution dust extinction map of the Barnard 59 complex in the Pipe Nebula. The map was constructed with the infrared color excess technique applied...
The California Molecular Cloud (2009)
Lada, Charles J., Lombardi, Marco, Alves, Joao F.
We present an analysis of wide-field infrared extinction maps of a region in Perseus just north of the Taurus-Auriga dark cloud complex. From this analysis we have identified a massive, nearby, but...
Currie, Thayne, Lada, Charles J., Plavchan, Peter, Robitaille, Thomas P., Irwin, Jonathan, Kenyon, Scott J.
Expanding upon the Infrared Array Camera (IRAC) survey from Dahm & Hillenbrand, we describe Spitzer IRAC and Multiband Imaging Photometer for Spitzer observations of the populous, 5 Myr old open...
IRS Characterization of a Debris Disk around an M-type star in NGC2547 (2009)
Teixeira, Paula S., Lada, Charles J., Wood, Kenneth, Robitaille, Thomas P., Luhman, Kevin L.
We present 5 to 15 micron Spitzer Infrared Spectrograph (IRS) low resolution spectral data of a candidate debris disk around an M4.5 star identified as a likely member of the ~40 Myr old cluster...
Currie, Thayne, Lada, Charles J., Plavchan, Peter, Robitaille, Thomas, Irwin, Jonathan, Kenyon, Scott J.
(Abridged) We describe Spitzer IRAC and MIPS observations of the populous, 5 Myr-old open cluster NGC 2362. Early/intermediate-type confirmed/candidate cluster members either have photospheric mid-IR...
2MASS wide field extinction maps: II. The Ophiuchus and the Lupus cloud complexe (2008)
Lombardi, Marco, Lada, Charles J., Alves, Joao
We present an extinction map of a ~1,700 deg sq region that encloses the Ophiuchus, the Lupus, and the Pipe dark complexes using 42 million stars from the Two Micron All Sky Survey (2MASS) point...
New M dwarf debris disk candidates in NGC 2547 (2008)
Forbrich, Jan, Lada, Charles J., Muench, August A., Teixeira, Paula S.
With only six known examples, M-dwarf debris disks are rare, even though M dwarfs constitute the majority of stars in the Galaxy. After finding a new M dwarf debris disk in a shallow mid-infrared...
Embedded Oscillating Starless Cores (2008)
Broderick, Avery E., Narayan, Ramesh, Keto, Eric, Lada, Charles J.
In a previous paper we demonstrated that non-radial hydrodynamic oscillations of a thermally-supported (Bonnor-Ebert) sphere embedded in a low-density, high-temperature medium persist for many...
Multiple CO Outflows in Circinus: The Churning of a Molecular Cloud (2007)
John Bally, Bo Reipurth, Charles J. Lada
We present a millimeter wave study of a cluster of bipolar CO outflows embedded in the western end of the Circinus molecular cloud complex, G317-4, that is traced by very high optical extinction. For...
Spitzer imaging of the jet driving the NGC 2264 G outflow (2007)
Teixeira, Paula S., McCoey, Carolyn, Fich, Michael, Lada, Charles J.
We present new infrared imaging of the NGC 2264 G protostellar outflow region, obtained with the InfraRed Array Camera (IRAC) on-board the Spitzer Space Telescope. A jet in the red outflow lobe...
Oscillating Starless Cores: The Nonlinear Regime (2007)
Broderick, Avery E., Keto, Eric, Lada, Charles J., Narayan, Ramesh
In a previous paper, we modeled the oscillations of a thermally-supported (Bonnor-Ebert) sphere as non-radial, linear perturbations following a standard analysis developed for stellar pulsations. The...
Maret, Sébastien, Bergin, Edwin A., Lada, Charles J.
We present observations of 13CO, C18O, HCO+, H13CO+, DCO+ and N2H+ line emission towards the Barnard 68 starless core. The line profiles are interpreted using a chemical network coupled with a...
The Nature of the Dense Core Population in the Pipe Nebula: Thermal Cores Under Pressure (2007)
Lada, Charles J., Muench, August A., Rathborne, Jill M., Alves, Joao F., Lombardi, Marco
In this paper we present the results of a systematic investigation of an entire population of starless dust cores within a single molecular cloud. Analysis of extinction data shows the cores to be...
Muench, August A., Lada, Charles J., Rathborne, Jill M., Alves, João F., Lombardi, M.
We present molecular-line observations of 94 dark cloud cores identified in the Pipe nebula through near-IR extinction mapping. Using the Arizona Radio Observatory 12m telescope, we obtained spectra...
A dense micro-cluster of Class 0 protostars in NGC 2264 D-MM1 (2007)
Teixeira, Paula S., Zapata, Luis A., Lada, Charles J.
We present sensitive and high angular resolution (~1") 1.3 mm continuum observations of the dusty core D-MM1 in the Spokes cluster in NGC 2264 using the Submillimeter Array. A dense micro-cluster of...
A Spitzer census of the IC 348 nebula (2007)
Muench, August A., Lada, Charles J., Luhman, K. L., Muzerolle, James, Young, Erick
We present a Spitzer based census of the IC 348 nebula and embedded star cluster. Our Spitzer census supplemented by ground based spectra has added 42 class II T-Tauri sources to the cluster...
2MASS wide field extinction maps - I. The Pipe nebula (2006)
Lombardi, Marco, Alves, Joao, Lada, Charles J.
We present a 8 deg x 6 deg, high resolution extinction map of the Pipe nebula using 4.5 million stars from the Two Micron All Sky Survey (2MASS) point source catalog. The use of NICER, a robust and...
Oscillations of starless cores (2006)
Keto, Eric, Broderick, Avery, Lada, Charles J., Narayan, Ramesh
If the split, asymmetric molecular spectral line profiles that are seen in many starless cores are interpreted as indicative of global collapse or expansion of the core then one possible implication...
Stellar Multiplicity and the IMF: Most Stars Are Single (2006)
In this short communication I compare recent findings suggesting a low binary star fraction for late type stars with knowledge concerning the forms of the stellar initial and present day mass...
Identifying Primordial Substructure in NGC 2264 (2005)
Teixeira, Paula S., Lada, Charles J., Young, Erick T., Marengo, Massimo, Muench, August, Muzerolle, James, ...
We present new Spitzer Space Telescope observations of the young cluster NGC2264. Observations at 24 micron with the Multiband Imaging Photometer has enabled us to identify the most highly embedded...
Covey, Kevin R., Greene, Thomas P., Doppmann, Greg W., Lada, Charles J., Wilking, Bruce A.
Recent observations of nearby star forming regions have offered evidence that young brown dwarfs undergo a period of mass accretion analogous to the T Tauri phase observed in young stars. Brown dwarf...
The Radial Velocity Distribution of Class I and Flat-Spectrum Protostars (2005)
Covey, Kevin R., Greene, Thomas P., Doppmann, Greg W., Lada, Charles J.
We analyze radial velocities for a sample of 31 Class I and flat spectrum protostars in Taurus-Auriga, rho Ophiuchi and Serpens for evidence of the global dynamical state of extremely young stellar...
From Dusty Filaments to Cores to Stars: An Infrared Extinction Study of Lupus 3 (2005)
Teixeira, Paula S., Lada, Charles J., Alves, Joao F.
We present deep NIR observations of a dense region of Lupus 3 obtained with ESO's NTT and VLT. Using the NICE method we construct a dust extinction map of the cloud, which reveals embedded globules,...
The Angular Momentum Content and Evolution of Class I and Flat-Spectrum Protostars (2005)
Covey, Kevin R., Greene, Thomas P., Doppmann, Greg W., Lada, Charles J.
We report on the angular momentum content of heavily embedded protostars based on our analysis of the projected rotation velocities (v sin i s) of 38 Class I/flat spectrum young stellar objects...
Embedded Clusters and the IMF (2004)
Despite valiant efforts over nearly five decades, attempts to determine the IMF over a complete mass range for galactic field stars and in open clusters have proved difficult. Infrared imaging...
Discovery of a Dusty Ring in the Coalsack: A Dense Core Caught in the Act of Formation? (2004)
Lada, Charles J., Huard, Tracy L., Crews, Lionel J., Alves, Joao F.
We present a new infrared extinction study of Globule 2, the most opaque molecular cloud core in the Coalsack complex. Using deep near-infrared imaging observations obtained with the ESO NTT we are...
Envelope Structure of Starless Core L694-2 Derived from a Near-Infrared Extinction Map (2003)
Harvey, Daniel W. A., Wilner, David J., Lada, Charles J., Myers, Philip C., Alves, Joao
We present a near-infrared extinction study of the dark globule L694-2, a starless core that shows strong evidence for inward motions in molecular line profiles. The J,H, and K band data were taken...
Embedded Clusters in Molecular Clouds (2003)
Lada, Charles J., Lada, Elizabeth A.
Stellar clusters are born embedded within giant molecular clouds (GMCs) and during their formation and early evolution are often only visible at infrared wavelengths, being heavily obscured by dust....
The Dynamical State of Barnard 68: A Thermally Supported, Pulsating Dark Cloud (2002)
Lada, Charles J., Bergin, Edwin A., Alves, Joao F., Huard, Tracy L.
We report sensitive, high resolution molecular-line observations of the dark cloud Barnard 68 obtained with the IRAM 30-m telescope. We analyze spectral-line observations of C18O, CS(2--1),...
Spectroscopic Detection of a Stellar-like Photosphere in an Accreting Protostar (2002)
Greene, Thomas P., Lada, Charles J.
We present the first spectrum of a highly veiled, strongly accreting protostar which shows photospheric absorption features and demonstrates the stellar nature of its central core. We find the...
Chandra Study of Young Stellar Objects in the NGC 1333 Star-forming Cloud (2002)
Getman, Konstantin V., Feigelson, Eric D., Townsley, Leisa, Bally, John, Lada, Charles J., Reipurth, Bo
NGC 1333, a highly active star formation region within the Perseus molecular cloud complex, has been observed with the ACIS-I detector on board the Chandra X-ray Observatory. In our image with a...
N2H+ and C18O Depletion in a Cold Dark Cloud (2002)
Bergin, Edwin A., Alves, Joao, Huard, Tracy L., Lada, Charles J.
We present sensitive, high angular resolution molecular-line observations of C18O and N2H+ toward the dark globule B68. We directly compare these data with the near-infrared extinction measurements...
Structure of Protostellar Collapse Candidate B335 Derived from Near-Infrared Extinction Maps (2001)
Harvey, Daniel W. A., Wilner, David J., Lada, Charles J., Myers, Philip C., Alves, Joao F., Chen, Hua
We present a near-infrared extinction study of the dark globule B335, a protostellar collapse candidate, using data from HST/NICMOS and the W.M. Keck Observatory. These data allow a new quantitative...
Disk Frequencies and Lifetimes in Young Clusters (2001)
Haisch Jr., Karl E., Lada, Elizabeth A., Lada, Charles J.
We report the results of the first sensitive L-band (3.5 micron) survey of the intermediate age (2.5 - 30 Myr) clusters NGC 2264, NGC 2362 and NGC 1960. We use JHKL colors to obtain a census of the...
Circumstellar Disks in the IC 348 Cluster (2001)
Haisch Jr., Karl E., Lada, Elizabeth A., Lada, Charles J.
We report the results of the first sensitive L-band (3.4 micron) imaging survey of the young IC 348 cluster in Perseus. In conjunction with previously acquired JHK (1.25, 1.65, 2.2 micron)...
A Mid-Infrared Study of the Young Stellar Population in the NGC 2024 Cluster (2000)
Haisch Jr., Karl E., Lada, Elizabeth A., Pina, Robert K., Telesco, Charles M., Lada, Charles J.
We present the results of the first broadband 10.8 um survey of the NGC 2024 cluster. The mid-infrared data were combined with our previously published JHKL photometry in order to construct spectral...
Lada, Charles J., Muench, August A., Haisch Jr., Karl E., Lada, Elizabeth A., Alves, Joao F., Tollestrup, Eric V., ...
We report the results of a sensitive near-infrared JHKL imaging survey of the Trapezium cluster in Orion. We use the JHKL colors to obtain a census of infrared excess stars in the cluster. Of (391)...
A Near-Infrared L Band Survey of the Young Embedded Cluster NGC 2024 (2000)
Haisch Jr., Karl E., Lada, Elizabeth A., Lada, Charles J.
We present the results of the first sensitive L band (3.4 micron) imaging study of the nearby young embedded cluster NGC 2024. Two separate surveys of the cluster were acquired in order to obtain a...
Modeling the Near-Infrared Luminosity Functions of Young Stellar Clusters (1999)
Muench, August A., Lada, Elizabeth A., Lada, Charles J.
We present the results of numerical experiments designed to evaluate the usefulness of near-infrared luminosity functions for constraining the Initial Mass Function (IMF) of young stellar...
Multiple CO Outflows in Circinus: The Churning of a Molecular Cloud (1998)
Bally, John, Reipurth, Bo, Lada, Charles J., Billawala, Youssef
We present a millimeter wave study of a cluster of bipolar CO outflows embedded in the western end of the Circinus molecular cloud complex, G317-4, that is traced by very high optical extinction. For...