A Near-Infrared Study of the Stellar Cluster: [DBS2003] 45 (2009)
Zhu, Qingfeng, Davies, Ben, Figer, Donald F., Trombley, Christine
We present a multi-wavelength photometric and spectroscopic study of a newly discovered candidate cluster [DBS2003] 45. Our H, Ks photometry confirms that [DBS2003] 45 is a cluster. An average visual...
Mass Distribution in the Central Few Parsecs of Our Galaxy (2009)
Oh, Seungkyung, Kim, Sungsoo S., Figer, Donald F.
We estimate the enclosed mass profile in the central 10 pc of the Milky Way by analyzing the infrared photometry and the velocity observations of dynamically relaxed stellar population in the...
Near-infrared spectra of Galactic stellar clusters detected on Spitzer/GLIMPSE images (2009)
Messineo, Maria, Davies, Ben, Ivanov, Valentin D., Figer, Donald F., Schuller, Frederic, Habing, Harm J., ...
We present near-infrared spectroscopic observations of massive stars in three stellar clusters located in the direction of the inner Galaxy. One of them, the Quartet, is a new discovery while the...
Discovery of a young massive stellar cluster near HESS J1813-178 (2008)
Messineo, Maria, Figer, Donald F., Davies, Ben, Rich, R. Michael, Valenti, E., Kudritzki, R. P.
We present the serendipitous discovery of a young stellar cluster in the Galactic disk at l=12deg. Using Keck/NIRSPEC, we obtained high- and low-resolution spectroscopy of several stars in the...
Radial Velocities of Stars in the Galactic Center (2008)
Zhu, Qingfeng, Kudritzki, Rolf P., Figer, Donald F., Najarro, Francisco, Merritt, David
We present results from K band slit scan observations of a ~20''x20'' region of the Galactic center (GC) in two separate epochs more than five years apart. The high resolution (R>=14,000)...
Over the past ten years, there has been a revolution in our understanding of massive young stellar clusters in the Galaxy. Initially, there were no known examples having masses $>10^4$, yet we now...
The Arches Cluster Mass Function (2006)
Kim, Sungsoo S., Figer, Donald F., Kudritzki, Rolf P., Najarro, F.
We have analyzed H and K_s-band images of the Arches cluster obtained using the NIRC2 instrument on Keck with the laser guide star adaptive optics (LGS AO) system. With the help of the LGS AO system,...
Discovery of an Extraordinarily Massive Cluster of Red Supergiants (2006)
Figer, Donald F., MacKenty, John, Robberto, Massimo, Smith, Kester, Najarro, Francisco, Kudritzki, Rolf P., ...
We report the discovery of an extraordinarily massive young cluster of stars in the Galaxy, having an inferred total initial cluster mass comparable to the most massive young clusters in the Galaxy....
Theoretical Isochrones with Extinction in the K Band. II. J - K versus K (2006)
Kim, Sungsoo S., Figer, Donald F., Lee, Myung Gyoon
We calculate theoretical isochrones in a consistent way for five filter pairs near the J and K band atmospheric windows (J-K, J-K', J-Ks, F110W-F205W, and F110W-F222M) using the Padova stellar...
High spectral resolution observations of the massive stars in the galactic center (2006)
Tanner, Angelle, Figer, Donald F., Najarro, Fransisco, Kudritzki, Rolf P., Gilmore, Diane, Morris, Mark, ...
High Spectral Resolution Observations of the Massive Stars in the Galactic Center (2005)
Tanner, Angelle, Figer, Donald F., Najarro, Paco, Kudritzki, Rolf P., Gilmore, Diane, Morris, Mark, ...
We present high-resolution near-infrared spectra, obtained with the NIRSPEC spectrograph on the W. M. Keck II Telescope, of a collection of hot, massive stars within the central 25 arcseconds of the...
Theoretical Isochrones with Extinction in the K Band (2005)
Kim, Sungsoo S., Figer, Donald F., Lee, Myung Gyoon, Oh, Seungkyung
We calculate theoretical isochrones in a consistent way for five filters (K, K', Ks, F205W, and F222M) in the atmospheric window between 1.9 and 2.5 micron using the Padova stellar evolutionary...
An upper limit to the masses of stars (2005)
There is no accepted upper mass limit for stars. Such a basic quantity escapes both theory, because of incomplete understanding of star formation, and observation, because of incompleteness in...
Massive Stars in the SGR 1806-20 Cluster (2005)
Figer, Donald F., Najarro, Francisco, Geballe, T. R., Blum, R. D., Kudritzki, Rolf P.
We report the discovery of additional hot and massive stars in the cluster surrounding the soft gamma repeater SGR 1806-20, based upon UKIRT and Keck near-infrared spectroscopy. Of the newly...
The Stellar Initial Mass Function in the Galactic Center (2004)
Massive stars define the upper limits of the star formation process, dominate the energetics of their local environs, and significantly affect the chemical evolution of galaxies. Their role in...
Metallicity in the Galactic Center: The Arches cluster (2004)
Najarro, Francisco, Figer, Donald F., Hillier, D. John, Kudritzki, Rolf P.
We present a quantitative spectral analysis of five very massive stars in the Arches cluster, located near the Galactic center, to determine stellar parameters, stellar wind properties and, most...
The Double-Lined Spectrum of LBV 1806-20 (2004)
Figer, Donald F., Najarro, Francisco, Kudritzki, Rolf P.
Despite much theoretical and observational progress, there is no known firm upper limit to the masses of stars. Our understanding of the interplay between the immense radiation pressure produced by...
Dynamical Friction of Galactic Center Star Clusters with an Intermediate-Mass Black Hole (2004)
Kim, Sungsoo S., Figer, Donald F., Morris, Mark
Numerical simulations of the dynamical friction suffered by a Galactic center star cluster harboring an intermediate-mass black hole (IMBH) have been performed. Gerhard has suggested that dynamical...
Young Massive Clusters in the Galactic Center (2004)
The three young clusters in the Galactic Center represent the closest examples of massive starbursts and they define the upper mass limit of the Galactic cluster mass functions. In this review, I...
Figer, Donald F., Rich, R. Michael, Kim, Sungsoo S., Morris, Mark, Serabyn, Eugene
We present Hubble Space Telescope (HST) Near-Infrared Camera and Multiobject Spectrometer (NICMOS) observations as evidence that continuous star formation has created much of the central stellar cusp...
High Precision Stellar Radial Velocities in the Galactic Center (2003)
We present radial velocities for 85 cool stars projected onto the central parsec of the Galaxy. The majority of these velocities have relative errors of $\sim$1 km/s, or a factor of $\sim$30-100...
• Advantages for Space Astronomy (2003)
Bernard J. Rauscher, Donald F. Figer, Michael Regan, Rockwell Status
• What is a Si-PIN detector?
Massive Stars in the Arches Cluster (2002)
Figer, Donald F., Najarro, Francisco, Gilmore, Diane, Morris, Mark, Kim, Sungsoo S., Serabyn, Eugene, ...
We present and use new spectra and narrow-band images, along with previously published broad-band images, of stars in the Arches cluster to extract photometry, astrometry, equivalent width, and...
Massive Stars and The Creation of our Galactic Center (2002)
Our Galactic Center hosts over 10% of the known massive stars in the Galaxy. The majority of these stars are located in three particularly massive clusters that formed within the past 5 Myr. While...
The Mass Function of the Arches Cluster from Gemini Adaptive Optics Data (2002)
Stolte, Andrea, Grebel, Eva K., Brandner, Wolfgang, Figer, Donald F.
We present the mass function (MF) of the Arches cluster obtained from ground-based adaptive optics data in comparison with results derived from HST/NICMOS data. A MF slope of Gamma = -0.8 +- 0.2 is...
The Altitude of an Infrared Bright Cloud Feature on Neptune from Near-Infrared Spectroscopy (2001)
Roe, Henry G., Graham, James R., McLean, Ian S., De Pater, Imke, Becklin, E. E., Figer, Donald F., ...
We present 2.03-2.30 micron near-infrared spectroscopy of Neptune taken 1999 June 2 (UT) with the W.M. Keck Observatory's near-infrared spectrometer (NIRSPEC) during the commissioning of the...
Starburst Clusters in Galactic Nuclei (2000)
Figer, Donald F., Morris, Mark
Galactic nuclei often harbor a disproportionately large amount of star formation activity with respect to their surrounding disks. Not coincidentally, the density of molecular material in galactic...
The Initial Mass Function in the Galactic Center (2000)
The Galactic Center contains the most massive young clusters in the Galaxy and serves as the closest example of a massive starburst region. Our recent results suggest that the Galactic Center...
Stellar Collisions and Mergers in the Galactic Center (2000)
Figer, Donald F., Kim, Sungsoo S.
Stars are most likely to merge or collide in regions of the highest stellar densities, and our own Galactic Center contains many stars packed into a relatively small volume -- even the ambient...
N-Body Simulations of Compact Young Clusters near the Galactic Center (2000)
Kim, Sungsoo S., Figer, Donald F., Lee, Hyung Mok, Morris, Mark
We investigate the dynamical evolution of compact young star clusters (CYCs) near the Galactic center (GC) using Aarseth's Nbody6 codes. The relatively small number of stars in the cluster...
J-Band Infrared Spectroscopy of a Sample of Brown Dwarfs Using Nirspec on Keck II (2000)
McLean, Ian S., Wilcox, Mavourneen K., Becklin, E. E., Figer, Donald F., Gilbert, Andrea M., Graham, James R., ...
Near-infrared spectroscopic observations of a sample of very cool, low-mass objects are presented with higher spectral resolution than in any previous studies. Six of the objects are L-dwarfs,...
Hot Stars and Cool Clouds: The Photodissociation Region M16 (2000)
Levenson, N. A., Graham, James R., McLean, Ian S., Becklin, E. E., Figer, Donald F., Gilbert, Andrea M., ...
We present high-resolution spectroscopy and images of a photodissociation region (PDR) in M16 obtained during commissioning of NIRSPEC on the Keck II telescope. PDRs play a significant role in...
Discovery of an Obscured Broad Line Region in the High Redshift Radio Galaxy MRC 2025-218 (2000)
Larkin, James E., McLean, Ian S., Graham, James R., Becklin, E. E., Figer, Donald F., Gilbert, Andrea M., ...
This paper presents infrared spectra taken with the newly commissioned NIRSPEC spectrograph on the Keck II Telescope of the High Redshift Radio Galaxy MRC 2025-218 (z=2.63) These observations...
2 micron Spectroscopy within 0.3 arcseconds of SgrA* (2000)
Figer, Donald F., Becklin, E. E., McLean, Ian S., Gilbert, Andrea M., Graham, James R., Larkin, James E., ...
We present moderate (R~$\approx$~2,700) and high resolution (R~$\approx$~22,000) 2.0$-$2.4 \micron\ spectroscopy of the central 0.1 square arcseconds of the Galaxy obtained with NIRSPEC, the facility...
High Resolution Infrared Imaging and Spectroscopy of the Pistol Nebula: Evidence for Ejection (1999)
Figer, Donald F., Morris, Mark, Geballe, T. R., Rich, R. Michael, Serabyn, Eugene, McLean, Ian S., ...
We present new NICMOS/HST infrared images and CGS4/UKIRT Br-alpha (4.05 um) spectroscopy of the Pistol Star and its associated nebula, finding strong evidence to support the hypothesis that the...
HST/NICMOS Observations of Massive Stellar Clusters Near the Galactic Center (1999)
Figer, Donald F., Kim, Sungsoo S., Morris, Mark, Serabyn, Eugene, Rich, R. Michael, McLean, Ian S.
We report Hubble Space Telescope (HST) Near-infrared Camera and Multi-object Spectrometer (NICMOS) observations of the Arches and Quintuplet clusters, two extraordinary young clusters near the...
Massive Stars in the Quintuplet Cluster (1999)
Figer, Donald F., McLean, Ian S., Morris, Mark
We present near-infrared photometry and K-band spectra of newly-identified massive stars in the Quintuplet Cluster, one of the three massive clusters projected within 50 pc of the Galactic Center. We...
Donald F. Figer, Mark Morris, T. R. Geballe, R. Michael Rich, Eugene Serabyn, Ian S. Mclean, ...
We present new infrared images, obtained with the Hubble Space Telescope (HST) Near-Infrared Camera and Multiobject Spectrometer (NICMOS), and Bra (4.05 km) spectroscopy, obtained using CGS4 on...