Search Results - "Geha, Marla"

Identifying AGNs in Low-mass Galaxies via Long-term Optical Variability by Baldassare, Vivienne F., Geha, Marla, Greene, Jenny

“…We present an analysis of the nuclear variability of ∼28,000 nearby (z < 0.15) galaxies with Sloan Digital Sky Survey (SDSS) spectroscopy in Stripe 82. We…”
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A STUDY IN BLUE: THE BARYON CONTENT OF ISOLATED LOW-MASS GALAXIES by Bradford, Jeremy D., Geha, Marla C., Blanton, Michael R.

“…ABSTRACT We study the baryon content of low-mass galaxies selected from the Sloan Digital Sky Survey (SDSS DR8), focusing on galaxies in isolated environments…”
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The Kinematics of the Ultra-faint Milky Way Satellites: Solving the Missing Satellite Problem by Simon, Joshua D, Geha, Marla

“…We present Keck DEIMOS spectroscopy of stars in eight of the newly discovered ultra-faint dwarf galaxies around the Milky Way. We measure the velocity…”
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AGN All the Way Down? AGN-like Line Ratios Are Common in the Lowest-mass Isolated Quiescent Galaxies by Dickey, Claire Mackay, Geha, Marla, Wetzel, Andrew, El-Badry, Kareem

“…We investigate the lowest-mass quiescent galaxies known to exist in isolated environments ( ; 1.5 Mpc from a more massive galaxy). This population may…”
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X-Ray Properties of Optically Variable Low-mass AGN Candidates by Messick, Alexander, Baldassare, Vivienne, Geha, Marla, Greene, Jenny

“…Abstract We present an X-ray analysis of 14 nearby ( z < 0.044) active galactic nuclei (AGNs) in low-mass galaxies ( M * ≲ 5 × 10 9 M ⊙ ) selected based on…”
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BREATHING FIRE: HOW STELLAR FEEDBACK DRIVES RADIAL MIGRATION, RAPID SIZE FLUCTUATIONS, AND POPULATION GRADIENTS IN LOW-MASS GALAXIES by El-Badry, Kareem, Wetzel, Andrew, Geha, Marla, Hopkins, Philip F., Kereš, Dusan, Chan, T. K., Faucher-Giguère, Claude-André

“…ABSTRACT We examine the effects of stellar feedback and bursty star formation on low-mass galaxies (Mstar = 2 × 106 − 5 × 1010 M ) using the Feedback in…”
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The SAGA Survey. I. Satellite Galaxy Populations around Eight Milky Way Analogs by Geha, Marla, Wechsler, Risa H., Mao, Yao-Yuan, Tollerud, Erik J., Weiner, Benjamin, Bernstein, Rebecca, Hoyle, Ben, Marchi, Sebastian, Marshall, Phil J., Muñoz, Ricardo, Lu, Yu

“…We present the survey strategy and early results of the "Satellites Around Galactic Analogs" (SAGA) Survey. The SAGA Survey's goal is to measure the…”
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A MegaCam Survey of Outer Halo Satellites. III. Photometric and Structural Parameters by Muñoz, Ricardo R., Côté, Patrick, Santana, Felipe A., Geha, Marla, Simon, Joshua D., Oyarzún, Grecco A., Stetson, Peter B., Djorgovski, S. G.

“…Abstract We present structural parameters from a wide-field homogeneous imaging survey of Milky Way satellites carried out with the MegaCam imagers on the 3.6…”
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The Proper Motion Field of the Small Magellanic Cloud: Kinematic Evidence for Its Tidal Disruption by Zivick, Paul, Kallivayalil, Nitya, van der Marel, Roeland P., Besla, Gurtina, Linden, Sean T., Koz owski, Szymon, Fritz, Tobias K., Kochanek, C. S., Anderson, J., Sohn, Sangmo Tony, Geha, Marla C., Alcock, Charles R.

“…We present a new measurement of the systemic proper motion of the Small Magellanic Cloud (SMC), based on an expanded set of 30 fields containing background…”
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HIGH-RESOLUTION SPECTROSCOPY OF EXTREMELY METAL-POOR STARS IN THE LEAST EVOLVED GALAXIES: BOÖTES II by Ji, Alexander P, Frebel, Anna, Simon, Joshua D, Geha, Marla

“…ABSTRACT We present high-resolution Magellan /MIKE spectra of the four brightest confirmed red giant stars in the ultra-faint dwarf galaxy Boötes II (Boo II)…”
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THE DISTRIBUTION OF ALPHA ELEMENTS IN ANDROMEDA DWARF GALAXIES by Vargas, Luis C, Geha, Marla C, Tollerud, Erik J

“…We present alpha to iron abundance ratios for 226 individual red giant branch stars in nine dwarf galaxies of the Andromeda (M31) satellite system. The…”
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THE QUENCHING OF THE ULTRA-FAINT DWARF GALAXIES IN THE REIONIZATION ERA by Brown, Thomas M, Tumlinson, Jason, Geha, Marla, Simon, Joshua D, Vargas, Luis C, Vandenberg, Don A, Kirby, Evan N, Kalirai, Jason S, Avila, Roberto J, Gennaro, Mario, Ferguson, Henry C, Munoz, Ricardo R, Guhathakurta, Puragra, Renzini, Alvio

“…We present new constraints on the star formation histories of six ultra-faint dwarf galaxies: Bootes I, Canes Venatici II, Coma Berenices, Hercules, Leo IV,…”
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Multi-element Abundance Measurements from Medium-resolution Spectra. I. The Sculptor Dwarf Spheroidal Galaxy by Kirby, Evan N, Guhathakurta, Puragra, Bolte, Michael, Sneden, Christopher, Geha, Marla C

“…We present measurements of Fe, Mg, Si, Ca, and Ti abundances for 388 radial velocity member stars in the Sculptor dwarf spheroidal galaxy (dSph), a satellite…”
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The Effect of AGNs on the Global H i Content of Isolated Low-mass Galaxies by Bradford, Jeremy D., Geha, Marla C., Greene, Jenny E., Reines, Amy E., Dickey, Claire M.

“…We investigate the global neutral hydrogen (H i) content of isolated galaxies selected from the SDSS spectroscopic survey with optical evidence of Active…”
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Multiple chemodynamic stellar populations of the Ursa Minor dwarf spheroidal galaxy by Pace, Andrew B, Kaplinghat, Manoj, Kirby, Evan, Simon, Joshua D, Tollerud, Erik, Muñoz, Ricardo R, Côté, Patrick, Djorgovski, S G, Geha, Marla

“…ABSTRACT We present a Bayesian method to identify multiple (chemodynamic) stellar populations in dwarf spheroidal galaxies (dSphs) using velocity, metallicity,…”
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A SLIPPERY SLOPE: SYSTEMATIC UNCERTAINTIES IN THE LINE WIDTH BARYONIC TULLY-FISHER RELATION by Bradford, Jeremy D., Geha, Marla C., Bosch, Frank C. van den

“…ABSTRACT The baryonic Tully-Fisher relation (BTFR) is both a valuable observational tool and a critical test of galaxy formation theory. We explore the…”
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Forecasts on the Dark Matter Density Profiles of Dwarf Spheroidal Galaxies with Current and Future Kinematic Observations by Guerra, Juan, Geha, Marla, Strigari, Louis E.

“…Abstract We forecast parameter uncertainties on the mass profile of a typical Milky Way dwarf spheroidal galaxy (dSph) using the spherical Jeans equation and…”
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The JWST Resolved Stellar Populations Early Release Science Program. II. Survey Overview by Weisz, Daniel R., McQuinn, Kristen B. W., Savino, Alessandro, Kallivayalil, Nitya, Anderson, Jay, Boyer, Martha L., Correnti, Matteo, Geha, Marla C., Dolphin, Andrew E., Sandstrom, Karin M., Cole, Andrew A., Williams, Benjamin F., Skillman, Evan D., Cohen, Roger E., Newman, Max J. B., Beaton, Rachael, Bressan, Alessandro, Bolatto, Alberto, Boylan-Kolchin, Michael, Brooks, Alyson M., Bullock, James S., Conroy, Charlie, Cooper, M. C., Dalcanton, Julianne J., Dotter, Aaron L., Fritz, Tobias K., Garling, Christopher T., Gennaro, Mario, Gilbert, Karoline M., Girardi, Léo, Johnson, Benjamin D., Johnson, L. Clifton, Kalirai, Jason S., Kirby, Evan N., Lang, Dustin, Marigo, Paola, Richstein, Hannah, Schlafly, Edward F., Schmidt, Judy, Tollerud, Erik J., Warfield, Jack T., Wetzel, Andrew

“…Abstract We present the JWST Resolved Stellar Populations Early Release Science (ERS) program. We obtained 27.5 hr of NIRCam and NIRISS imaging of three…”
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The JWST Resolved Stellar Populations Early Release Science Program. V. DOLPHOT Stellar Photometry for NIRCam and NIRISS by Weisz, Daniel R., Dolphin, Andrew E., Savino, Alessandro, McQuinn, Kristen B. W., Newman, Max J. B., Williams, Benjamin F., Kallivayalil, Nitya, Anderson, Jay, Boyer, Martha L., Correnti, Matteo, Geha, Marla C., Sandstrom, Karin M., Cole, Andrew A., Warfield, Jack T., Skillman, Evan D., Cohen, Roger E., Beaton, Rachael, Bressan, Alessandro, Bolatto, Alberto, Boylan-Kolchin, Michael, Brooks, Alyson M., Bullock, James S., Conroy, Charlie, Cooper, Michael C., Dalcanton, Julianne J., Dotter, Aaron L., Fritz, Tobias K., Garling, Christopher T., Gennaro, Mario, Gilbert, Karoline M., Girardi, Leo, Johnson, Benjamin D., Johnson, L. Clifton, Kalirai, Jason, Kirby, Evan N., Lang, Dustin, Marigo, Paola, Richstein, Hannah, Schlafly, Edward F., Tollerud, Erik J., Wetzel, Andrew

“…Abstract We present NIRCam and NIRISS modules for DOLPHOT, a widely used crowded-field stellar photometry package. We describe details of the modules including…”
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A Noninteracting Galactic Black Hole Candidate in a Binary System with a Main-sequence Star by Chakrabarti, Sukanya, Simon, Joshua D., Craig, Peter A., Reggiani, Henrique, Brandt, Timothy D., Guhathakurta, Puragra, Dalba, Paul A., Kirby, Evan N., Chang, Philip, Hey, Daniel R., Savino, Alessandro, Geha, Marla, Thompson, Ian B.

“…Abstract We describe the discovery of a solar neighborhood ( d = 468 pc) binary system with a main-sequence sunlike star and a massive noninteracting black…”
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