Search Results - "Caldwell, Nelson"

A Nitrogen-rich Supernova Remnant in M31: Interaction with the Circumstellar Medium at Late Times by Caldwell, Nelson, Raymond, John C.

“…Abstract We present the discovery of a supernova remnant in M31 which is unlike any other remnant known in that galaxy. An optical ground-based spectrum of…”
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Crater 2: An Extremely Cold Dark Matter Halo by Caldwell, Nelson, Walker, Matthew G., Mateo, Mario, Olszewski, Edward W., Koposov, Sergey, Belokurov, Vasily, Torrealba, Gabriel, Geringer-Sameth, Alex, Johnson, Christian I.

“…We present results from MMT/Hectochelle spectroscopy of 390 red giant candidate stars along the line of sight to the recently discovered Galactic satellite…”
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A Deeper Look at the New Milky Way Satellites: Sagittarius II, Reticulum II, Phoenix II, and Tucana III by Mutlu-Pakdil, Burçin, Sand, David J., Carlin, Jeffrey L., Spekkens, Kristine, Caldwell, Nelson, Crnojević, Denija, Hughes, Allison K., Willman, Beth, Zaritsky, Dennis

“…Abstract We present deep Magellan /Megacam stellar photometry of four recently discovered faint Milky Way satellites: Sagittarius II (Sgr II), Reticulum II…”
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THE METALLICITY PROFILE OF M31 FROM SPECTROSCOPY OF HUNDREDS OF H II REGIONS AND PNe by Sanders, Nathan E, Caldwell, Nelson, McDowell, Jonathan, Harding, Paul

“…The oxygen abundance gradients among nebular emission line regions in spiral galaxies have been used as important constraints for models of chemical evolution…”
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Nearby Early-type Galactic Nuclei at High Resolution: Dynamical Black Hole and Nuclear Star Cluster Mass Measurements by Nguyen, Dieu D., Seth, Anil C., Neumayer, Nadine, Kamann, Sebastian, Voggel, Karina T., Cappellari, Michele, Picotti, Arianna, Nguyen, Phuong M., Böker, Torsten, Debattista, Victor, Caldwell, Nelson, McDermid, Richard, Bastian, Nathan, Ahn, Christopher C., Pechetti, Renuka

“…We present a detailed study of the nuclear star clusters (NSCs) and massive black holes (BHs) of four of the nearest low-mass early-type galaxies: M32, NGC…”
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Improved Dynamical Constraints on the Mass of the Central Black Hole in NGC 404 by Nguyen, Dieu D., Seth, Anil C., Brok, Mark den, Neumayer, Nadine, Cappellari, Michele, Barth, Aaron J., Caldwell, Nelson, Williams, Benjamin F., Binder, Breanna

“…We explore the nucleus of the nearby 109 M early-type galaxy, NGC 404, using Hubble Space Telescope (HST)/STIS spectroscopy and WFC3 imaging. We first present…”
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The Distance to the S147 Supernova Remnant by Kochanek, C. S., Raymond, John C., Caldwell, Nelson

“…In the absence of a parallax distance to a pulsar or a surviving binary in a supernova remnant (SNR), distances to Galactic SNRs are generally very uncertain…”
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Hubble Space Telescope Observations of NGC 253 Dwarf Satellites: Three Ultra-faint Dwarf Galaxies by Mutlu-Pakdil, Burçin, Sand, David J., Crnojević, Denija, Jones, Michael G., Caldwell, Nelson, Guhathakurta, Puragra, Seth, Anil C., Simon, Joshua D., Spekkens, Kristine, Strader, Jay, Toloba, Elisa

“…Abstract We present deep Hubble Space Telescope (HST) imaging of five faint dwarf galaxies associated with the nearby spiral NGC 253 (D ≈ 3.5 Mpc). Three of…”
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TIDAL SIGNATURES IN THE FAINTEST MILKY WAY SATELLITES: THE DETAILED PROPERTIES OF LEO V, PISCES II, AND CANES VENATICI II by Sand, David J., Strader, Jay, Willman, Beth, Zaritsky, Dennis, McLeod, Brian, Caldwell, Nelson, Seth, Anil, Olszewski, Edward

“…We present deep wide-field photometry of three recently discovered faint Milky Way (MW) satellites: Leo V, Pisces II, and Canes Venatici II. Our main goals are…”
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Abundance Analysis of Stars at Large Radius in the Sextans Dwarf Spheroidal Galaxy by Roederer, Ian U., Pace, Andrew B., Placco, Vinicius M., Caldwell, Nelson, Koposov, Sergey E., Mateo, Mario, Olszewski, Edward W., Walker, Matthew G.

“…Abstract We present the stellar parameters and chemical abundances of 30 elements for five stars located at large radii (3.5–10.7 times the half-light radius)…”
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Discovery of the Magellanic Stellar Stream Out to 100 kpc by Chandra, Vedant, Naidu, Rohan P., Conroy, Charlie, Bonaca, Ana, Zaritsky, Dennis, Cargile, Phillip A., Caldwell, Nelson, Johnson, Benjamin D., Han, Jiwon Jesse, Ting, Yuan-Sen

“…Abstract The Magellanic Stream (MS)—an enormous ribbon of gas spanning 140° of the southern sky trailing the Magellanic Clouds—has been exquisitely mapped in…”
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Magellan/M2FS and MMT/Hectochelle Spectroscopy of Dwarf Galaxies and Faint Star Clusters within the Galactic Halo by Walker, Matthew G., Caldwell, Nelson, Mateo, Mario, Olszewski, Edward W., Pace, Andrew B., Bailey, John I., Koposov, Sergey E., Roederer, Ian U.

“…Abstract We present spectroscopic data for 16,369 stellar targets within and/or toward 38 dwarf spheroidal galaxies and faint star clusters within the Milky…”
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The Cygnus Loop: Shock Precursors and Electron–Ion Equilibration by Raymond, John C., Seok, Ji Yeon, Koo, Bon-Chul, Chilingarian, Igor V., Grishin, Kirill, Caldwell, Nelson, Xie, Min, Fesen, Robert

“…Abstract The outermost edges of some supernova remnants are marked by filaments of pure Balmer line emission produced by nonradiative shock fronts. The H α…”
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New Velocity Measurements of NGC 5128 Globular Clusters Out to 130 kpc: Outer Halo Kinematics, Substructure, and Dynamics by Hughes, Allison K., Sand, David J., Seth, Anil, Strader, Jay, Lidman, Chris, Voggel, Karina, Dumont, Antoine, Crnojević, Denija, Mateo, Mario, Caldwell, Nelson, Forbes, Duncan A., Pearson, Sarah, Guhathakurta, Puragra, Toloba, Elisa

“…Abstract We present new radial velocity measurements from the Magellan and the Anglo-Australian Telescopes for 175 previously known and 121 newly confirmed…”
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A Lower Limit on the Mass of Our Galaxy from the H3 Survey by Zaritsky, Dennis, Conroy, Charlie, Zhang, Huanian, Naidu, Rohan P., Bonaca, Ana, Caldwell, Nelson, Cargile, Phillip A., Johnson, Benjamin D.

“…The timing argument provides a lower limit on the mass of the Milky Way. Using a sample of 32 stars at R > 60 kpc drawn from the H3 Spectroscopic Survey and…”
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The Faint Satellite System of NGC 253: Insights into Low-density Environments and No Satellite Plane by Mutlu-Pakdil, Burçin, Sand, David J., Crnojević, Denija, Bennet, Paul, Jones, Michael G., Spekkens, Kristine, Karunakaran, Ananthan, Zaritsky, Dennis, Caldwell, Nelson, Fielder, Catherine E., Guhathakurta, Puragra, Seth, Anil C., Simon, Joshua D., Strader, Jay, Toloba, Elisa

“…Abstract We have conducted a systematic search around the Milky Way (MW) analog NGC 253 ( D = 3.5 Mpc), as a part of the Panoramic Imaging Survey of Centaurus…”
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ELECTRON-ION EQUILIBRIUM AND SHOCK PRECURSORS IN THE NORTHEAST LIMB OF THE CYGNUS LOOP by Medina, Amber A, Raymond, John C, Edgar, Richard J, Caldwell, Nelson, Fesen, Robert A, Milisavljevic, Dan

“…We present an observational study using high-resolution echelle spectroscopy of collisionless shocks in the Cygnus Loop supernova remnant. Measured H alpha…”
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The Rotating Nuclear Star Cluster in NGC 4244 by Seth, Anil C, Blum, Robert D, Bastian, Nate, Caldwell, Nelson, Debattista, Victor P

“…We present observations of the nuclear star cluster in the nearby edge-on spiral galaxy NGC 4244 using the Gemini Near-Infrared Integral Field Spectrograph…”
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Hectospec, the MMT’s 300 Optical Fiber‐Fed Spectrograph by Fabricant, Daniel, Fata, Robert, Roll, John, Hertz, Edward, Caldwell, Nelson, Gauron, Thomas, Geary, John, McLeod, Brian, Szentgyorgyi, Andrew, Zajac, Joseph, Kurtz, Michael, Barberis, Jack, Bergner, Henry, Brown, Warren, Conroy, Maureen, Eng, Roger, Geller, Margaret, Goddard, Richard, Honsa, Michael, Mueller, Mark, Mink, Douglas, Ordway, Mark, Tokarz, Susan, Woods, Deborah, Wyatt, William, Epps, Harland, Dell’Antonio, Ian

“…The Hectospec is a 300 optical fiber fed spectrograph commissioned at the MMT in the spring of 2004. In the configuration pioneered by the Autofib instrument…”
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PHAT STELLAR CLUSTER SURVEY. I. YEAR 1 CATALOG AND INTEGRATED PHOTOMETRY by JOHNSON, L. Clifton, SETH, Anil C, SARAJEDINI, Ata, WEISZ, Daniel R, WILLIAMS, Benjamin F, BEERMAN, Lori C, BIANCHI, Luciana, DOLPHIN, Andrew E, GIRARDI, Léo, GUHATHAKURTA, Puragra, KAURAI, Jason, LANG, Dustin, DALCANTON, Julianne J, MONACHESI, Antonela, NANDA, Sanjay, RIX, Hans-Walter, SKILLMAN, Evan D, CALDWELL, Nelson, FOUESNEAU, Morgan, GOULIERMIS, Dimitrios A, HODGE, Paul W, LARSEN, SØren S, OLSEN, Knut A. G, SAN ROMAN, Izaskun

“…The Panchromatic Hubble Andromeda Treasury (PHAT) survey is an ongoing Hubble Space Telescope (HST) multi-cycle program to obtain high spatial resolution…”
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