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6,469 full-text articles. Page 192 of 198.

Herschel/Hifi Measurements Of The Ortho/Para Ratio In Water Towards Sagittarius B2(M) And W31c*, DC Lis, TG Phillips, PF Goldsmith, Da Neufeld, E Herbst, C Comito, P Schilke, HSP Muller, EA Bergin, M Gerin, TA Bell, M Emprechtinger, JH Black, GA Blake, F Boulanger, E Caux, C Ceccarelli, J Cernicharo, A Coutens, NR Crockett, F Daniel, E Dartois, M De Luca, ML Dubernet, P Encrenaz, E Falgarone, TR Geballe, B Godard, TF Giesen, JR Goicoechea, C Gry, H Gupta, P Hennebelle, P Hily-Blant, R Kolos, J Krelowski, C Joblin, D Johnstone, M Kazmierczak, SD Lord, S Maret, PG Martin, J Martin-Pintado, GJ Melnick, KM Menten, R Monje, B Mookerjea, P Morris, JA Murphy, V Ossenkopf, JC Pearson, M Perault, C Persson, R Plume, SL Qin, M Salez, S Schlemmer, M Schmidt, P Sonnentrucker, J Stutzski, D Teyssier, N Trappe, FFS van der Tak, C Vastel, S Wang, HW Yorke, S Yu, J Zmuidzinas, A Boogert, NR Erickson, A Karpov, J Kooi, FW Maiwald, R Schieder, P Zaal 2010 University of Massachusetts - Amherst

Herschel/Hifi Measurements Of The Ortho/Para Ratio In Water Towards Sagittarius B2(M) And W31c*, Dc Lis, Tg Phillips, Pf Goldsmith, Da Neufeld, E Herbst, C Comito, P Schilke, Hsp Muller, Ea Bergin, M Gerin, Ta Bell, M Emprechtinger, Jh Black, Ga Blake, F Boulanger, E Caux, C Ceccarelli, J Cernicharo, A Coutens, Nr Crockett, F Daniel, E Dartois, M De Luca, Ml Dubernet, P Encrenaz, E Falgarone, Tr Geballe, B Godard, Tf Giesen, Jr Goicoechea, C Gry, H Gupta, P Hennebelle, P Hily-Blant, R Kolos, J Krelowski, C Joblin, D Johnstone, M Kazmierczak, Sd Lord, S Maret, Pg Martin, J Martin-Pintado, Gj Melnick, Km Menten, R Monje, B Mookerjea, P Morris, Ja Murphy, V Ossenkopf, Jc Pearson, M Perault, C Persson, R Plume, Sl Qin, M Salez, S Schlemmer, M Schmidt, P Sonnentrucker, J Stutzski, D Teyssier, N Trappe, Ffs Van Der Tak, C Vastel, S Wang, Hw Yorke, S Yu, J Zmuidzinas, A Boogert, Nr Erickson, A Karpov, J Kooi, Fw Maiwald, R Schieder, P Zaal

Astronomy Department Faculty Publication Series

We present Herschel/HIFI observations of the fundamental rotational transitions of ortho- and para-H216O and H218O in absorption towards Sagittarius B2(M) and W31C. The ortho/para ratio in water in the foreground clouds on the line of sight towards these bright continuum sources is generally consistent with the statistical high-temperature ratio of 3, within the observational uncertainties. However, somewhat unexpectedly, we derive a low ortho/para ratio of 2.35 ± 0.35, corresponding to a spin temperature of ~27 K, towards Sagittarius B2(M) at velocities of the expanding molecular ring. Water molecules ...


Submillimeter Array Identification Of The Millimeter-Selected Galaxy Ssa22-Aztec1: A Protoquasar In A Protocluster?, Y Tamura, D Iono, DJ Wilner, M Kajisawa, YK Uchimoto, DM Alexander, A Chung, H Ezawa, B Hatsukade, T Hayashino, DH Hughes, T Ichikawa, S Irkarashi, R Kawabe, K Kohno, BD Lehmer, Y Matsuda, K Nakanishi, T Takata, GW Wilson, T Yamada, Min Yun 2010 University of Massachusetts - Amherst

Submillimeter Array Identification Of The Millimeter-Selected Galaxy Ssa22-Aztec1: A Protoquasar In A Protocluster?, Y Tamura, D Iono, Dj Wilner, M Kajisawa, Yk Uchimoto, Dm Alexander, A Chung, H Ezawa, B Hatsukade, T Hayashino, Dh Hughes, T Ichikawa, S Irkarashi, R Kawabe, K Kohno, Bd Lehmer, Y Matsuda, K Nakanishi, T Takata, Gw Wilson, T Yamada, Min Yun

Astronomy Department Faculty Publication Series

We present results from Submillimeter Array (SMA) 860 μm subarcsecond astrometry and multiwavelength observations of the brightest millimeter (S 1.1mm = 8.4 mJy) source, SSA22-AzTEC1, found near the core of the SSA22 protocluster that is traced by Lyα-emitting galaxies at z = 3.09. We identify a 860 μm counterpart with a flux density of S 860 μm = 12.2 ± 2.3 mJy and absolute positional accuracy that is better than 03. At the SMA position, we find radio-to-mid-infrared counterparts, whilst no object is found in Subaru optical and near-infrared deep images at wavelengths ≤1 μm (J > 25.4 in ...


An Investigation Of The Dust Content In The Galaxy Pair Ngc 1512/1510 From Near-Infrared To Millimeter Wavelengths, GL Liu, D Calzetti, MS Yun, GW Wilson, BT Draine, K Scott, J Austermann, T Perera, D Hughes, I Aretxaga, K Kohno, R Kawabe, H Ezawa 2010 University of Massachusetts Amherst

An Investigation Of The Dust Content In The Galaxy Pair Ngc 1512/1510 From Near-Infrared To Millimeter Wavelengths, Gl Liu, D Calzetti, Ms Yun, Gw Wilson, Bt Draine, K Scott, J Austermann, T Perera, D Hughes, I Aretxaga, K Kohno, R Kawabe, H Ezawa

Astronomy Department Faculty Publication Series

We combine new ASTE/AzTEC 1.1 mm maps of the galaxy pair NGC 1512/1510 with archival Spitzer IRAC and MIPS images covering the wavelength range 3.6-160 μm from the SINGS project. The availability of the 1.1 mm map enables us to measure the long-wavelength tail of the dust emission in each galaxy, and in sub-galactic regions in NGC 1512, and to derive accurate dust masses. The two galaxies form a pair consisting of a large, high-metallicity spiral (NGC 1512) and a low-metallicity, blue compact dwarf (NGC 1510), which we use to compare similarities and contrast differences ...


Variable O Vi And N V Emission From The X-Ray Binary Lmc X-3: Heating Of The Black Hole Companion*, L Song, TM Tripp, QD Wang, Y Yao, W Cui, Y Xue, JA Orosz, D Steeghs, JF Steiner, MAP Torres, JE McClintock 2010 University of Massachusetts - Amherst

Variable O Vi And N V Emission From The X-Ray Binary Lmc X-3: Heating Of The Black Hole Companion*, L Song, Tm Tripp, Qd Wang, Y Yao, W Cui, Y Xue, Ja Orosz, D Steeghs, Jf Steiner, Map Torres, Je Mcclintock

Astronomy Department Faculty Publication Series

Based on high-resolution ultraviolet spectroscopy obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) and the Cosmic Origins Spectrograph, we present new detections of O VI and N V emission from the black hole X-ray binary (XRB) system LMC X-3. We also update the ephemeris of the XRB using recent radial velocity measurements obtained with the echelle spectrograph on the Magellan-Clay telescope. We observe significant velocity variability of the UV emission, and we find that the O VI and N V emission velocities follow the optical velocity curve of the XRB. Moreover, the O VI and N V intensities regularly decrease ...


Herschel Observations Of Ortho- And Para-Oxidaniumyl (H2o+) In Spiral Arm Clouds Toward Sagittarius B2(M) *,**, P Schilke, C Comito, HSP Muller, EA Bergin, E Herbst, DC Lis, DA Neufeld, TG Phillips, TA Bell, GA Blake, S Cabrit, E Caux, C Ceccarelli, J Cernicharo, NR Crockett, F Daniel, ML Dubernet, M Emprechtinger, P Encrenaz, E Falgarone, M Gerin, TF Giesen, JR Goicoechea, PF Goldsmith, H Gupta, C Jobin, D Johnstone, WD Langer, WB Latter, SD Lord, S Maret, PG Martin, GJ Melnick, KM Menten, P Morris, JA Murphy, V Ossenkopf, L Pagani, JC Pearson, M Perault, R Plume, SL Qin, M Salez, S Schlemmer, J Stutzski, N Trappe, FFS van der Tak, C Vastel, S Wang, HW Yorke, S Yu, NR Erickson, FW Maiwald, J Kooi, A Karpov, J Zmuidzinas, A Boogert, R Schieder, P Zaal 2010 University of Massachusetts - Amherst

Herschel Observations Of Ortho- And Para-Oxidaniumyl (H2o+) In Spiral Arm Clouds Toward Sagittarius B2(M) *,**, P Schilke, C Comito, Hsp Muller, Ea Bergin, E Herbst, Dc Lis, Da Neufeld, Tg Phillips, Ta Bell, Ga Blake, S Cabrit, E Caux, C Ceccarelli, J Cernicharo, Nr Crockett, F Daniel, Ml Dubernet, M Emprechtinger, P Encrenaz, E Falgarone, M Gerin, Tf Giesen, Jr Goicoechea, Pf Goldsmith, H Gupta, C Jobin, D Johnstone, Wd Langer, Wb Latter, Sd Lord, S Maret, Pg Martin, Gj Melnick, Km Menten, P Morris, Ja Murphy, V Ossenkopf, L Pagani, Jc Pearson, M Perault, R Plume, Sl Qin, M Salez, S Schlemmer, J Stutzski, N Trappe, Ffs Van Der Tak, C Vastel, S Wang, Hw Yorke, S Yu, Nr Erickson, Fw Maiwald, J Kooi, A Karpov, J Zmuidzinas, A Boogert, R Schieder, P Zaal

Astronomy Department Faculty Publication Series

H2O+ has been observed in its ortho- and para- states toward the massive star forming core Sgr B2(M), located close to the Galactic center. The observations show absorption in all spiral arm clouds between the Sun and Sgr B2. The average o/p ratio of H2O+ in most velocity intervals is 4.8, which corresponds to a nuclear spin temperature of 21 K. The relationship of this spin temperature to the formation temperature and current physical temperature of the gas hosting H2O+ is discussed, but no firm conclusion is reached. In the velocity ...


Optical Spectroscopy And Nebular Oxygen Abundances Of The Spitzer/Sings Galaxies, J Moustakas, R Kennicutt, C Tremontt, D Dale5, J Smith, D Calzetti 2010 University of Massachusetts - Amherst

Optical Spectroscopy And Nebular Oxygen Abundances Of The Spitzer/Sings Galaxies, J Moustakas, R Kennicutt, C Tremontt, D Dale5, J Smith, D Calzetti

Astronomy Department Faculty Publication Series

We present intermediate-resolution optical spectrophotometry of 65 galaxies obtained in support of the Spitzer Infrared Nearby Galaxies Survey (SINGS). For each galaxy we obtain a nuclear, circumnuclear, and semi-integrated optical spectrum designed to coincide spatially with mid- and far-infrared spectroscopy from the Spitzer Space Telescope. We make the reduced, spectrophotometrically calibrated one-dimensional spectra, as well as measurements of the fluxes and equivalent widths of the strong nebular emission lines, publically available. We use optical emission-line ratios measured on all three spatial scales to classify the sample into star-forming, active galactic nuclei (AGN), and galaxies with a mixture of star formation ...


Total Infrared Luminosity Estimation Of Resolved And Unresolved Galaxies, M Boquien, G Bendo, D Calzetti, D Dale, C Engelbracht, R Kennicutt, JC Lee, L van Zee, J Moustakas 2010 University of Massachusetts Amherst

Total Infrared Luminosity Estimation Of Resolved And Unresolved Galaxies, M Boquien, G Bendo, D Calzetti, D Dale, C Engelbracht, R Kennicutt, Jc Lee, L Van Zee, J Moustakas

Astronomy Department Faculty Publication Series

The total infrared (TIR) luminosity from galaxies can be used to examine both star formation and dust physics. We provide here new relations to estimate the TIR luminosity from various Spitzer bands, in particular from the 8 μm and 24 μm bands. To do so, we use data for 45'' subregions within a subsample of nearby face-on spiral galaxies from the Spitzer Infrared Nearby Galaxies Survey (SINGS) that have known oxygen abundances as well as integrated galaxy data from the SINGS, the Local Volume Legacy survey (LVL), and Engelbracht et al. samples. Taking into account the oxygen abundances of the ...


X-Ray Spectroscopy Of Galactic Hot Gas Along The Pks 2155$-$304 Sight Line, T Hagihara, Y Yao, NY Yamasaki, K Mitsuda, QD Wang, Y Takei, T Yoshino, D McCammon 2010 University of Massachusetts - Amherst

X-Ray Spectroscopy Of Galactic Hot Gas Along The Pks 2155$-$304 Sight Line, T Hagihara, Y Yao, Ny Yamasaki, K Mitsuda, Qd Wang, Y Takei, T Yoshino, D Mccammon

Astronomy Department Faculty Publication Series

We present a detailed spectroscopic study of the hot gas in the Galactic halo toward the direction of a blazer PKS 2155304 ( 0.117). The OVII and OVIII absorption lines were measured with the Low and High Energy Transmission Grating Spectrographs aboard Chandra, and the OVII, OVIII, and NeIX emission lines produced in an adjacent field of the PKS 2155304 direction were observed with the X-ray Imaging Spectrometer aboard Suzaku. Assuming vertically exponential distributions of the gas temperature and the density, we performed a combined analysis of the absorption and emission data. The gas temperature and the density at the ...


Dust Emission And Star Formation In Stephan's Quintet, G Natale, RJ Tuffs, CK Xu, CC Popescu, J Fischera, U Lisenfeld, N Lu, P Appleton, M Dopita, P-A Duc, W Reach, J Sulentic, Min Yun 2010 University of Massachusetts - Amherst

Dust Emission And Star Formation In Stephan's Quintet, G Natale, Rj Tuffs, Ck Xu, Cc Popescu, J Fischera, U Lisenfeld, N Lu, P Appleton, M Dopita, P-A Duc, W Reach, J Sulentic, Min Yun

Astronomy Department Faculty Publication Series

We analyze a comprehensive set of MIR/FIR observations of Stephan's Quintet (SQ), taken with the Spitzer Space Telescope. Our study reveals the presence of a luminous (L IR 4.6 × 1043 erg s-1) and extended component of infrared dust emission, not connected with the main bodies of the galaxies, but roughly coincident with the X-ray halo of the group. We fitted the inferred dust emission spectral energy distribution of this extended source and the other main infrared emission components of SQ, including the intergalactic shock, to elucidate the mechanisms powering the dust and polycyclic aromatic hydrocarbon ...


Missing-Iron Problem And Type Ia Supernova Enrichment Of Hot Gas In Galactic Spheroids, S Tang, QD Wang 2010 University of Massachusetts - Amherst

Missing-Iron Problem And Type Ia Supernova Enrichment Of Hot Gas In Galactic Spheroids, S Tang, Qd Wang

Astronomy Department Faculty Publication Series

Type Ia supernovae (Ia SNe) provide a rich source of iron for hot gas in galactic stellar spheroids. However, the expected supersolar iron abundance of the hot gas is not observed. Instead, X-ray observations often show decreasing iron abundance towards galactic central regions, where the Ia SN enrichment is expected to be the highest. We examine the cause of this missing-iron problem by studying the enrichment process and its effect on X-ray abundance measurements of the hot gas. The evolution of Ia SN iron ejecta is simulated in the context of galaxy-wide hot gas outflows, in both supersonic and subsonic ...


Supernova Remnants And The Interstellar Medium Of M83: Imaging And Photometry With The Wide Field Camera 3 On The Hubble Space Telescope, MA Dopita, WP Blair, KS Long, M Mutchler, BC Whitmore, KD Kuntz, B Balick, HE Bond, D Calzetti, M Carollo, M Disney, JA Frogel, R O'Connell, D Hall, JA Holtzman, RA Kimble, J MacKenty, P McCarthy, F Paresce, A Saha, J Silk, M Sirianni, J Trauger, AR Walker, R Windhorst, E Young 2010 University of Massachusetts Amherst

Supernova Remnants And The Interstellar Medium Of M83: Imaging And Photometry With The Wide Field Camera 3 On The Hubble Space Telescope, Ma Dopita, Wp Blair, Ks Long, M Mutchler, Bc Whitmore, Kd Kuntz, B Balick, He Bond, D Calzetti, M Carollo, M Disney, Ja Frogel, R O'Connell, D Hall, Ja Holtzman, Ra Kimble, J Mackenty, P Mccarthy, F Paresce, A Saha, J Silk, M Sirianni, J Trauger, Ar Walker, R Windhorst, E Young

Astronomy Department Faculty Publication Series

We present Wide Field Camera 3 images taken with the Hubble Space Telescope within a single field in the southern grand design star-forming galaxy M83. Based on their size, morphology, and photometry in continuum-subtracted Hα, [S II], Hβ, [O III], and [O II] filters, we have identified 60 supernova remnant (SNR) candidates, as well as a handful of young ejecta-dominated candidates. A catalog of these remnants, their sizes and, where possible, their Hα fluxes are given. Radiative ages and pre-shock densities are derived from those SNRs that have good photometry. The ages lie in the range 2.62 < log (τrad/yr) < 5.0, and the pre-shock densities at the blast wave range over 0.56 < n 0/cm-3 < 1680. Two populations of SNRs have been discovered. These divide into a nuclear and spiral arm group and an inter-arm population. We infer an arm to inter-arm density contrast of 4. The surface flux in diffuse X-rays is correlated with the inferred pre-shock density, indicating that the warm interstellar medium (ISM) is pressurized by the hot X-ray plasma. We also find that the ISM in the nuclear region of M83 is characterized by a very high porosity and pressure, and infer an SNR rate of 1 per 70-150 yr for the nuclear (R < 300 pc) region. On the basis of the number of SNRs detected and their radiative ages, we infer that the lower mass of Type II SNe in M83 is M min = 16+7 –5 M . Finally, we give evidence for the likely detection of the remnant of the historical supernova, SN1968L.


X-Ray Emission From The Sombrero Galaxy: Discrete Sources, Z Li, LR Spitler, C Jones, WR Forman, RP Kraft, RD Stefano, S Tang, QD Wang, M Gilfanov, M Revnivtsev 2010 University of Massachusetts - Amherst

X-Ray Emission From The Sombrero Galaxy: Discrete Sources, Z Li, Lr Spitler, C Jones, Wr Forman, Rp Kraft, Rd Stefano, S Tang, Qd Wang, M Gilfanov, M Revnivtsev

Astronomy Department Faculty Publication Series

We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L X 1037 erg s–1 and a field of view covering a galactocentric radius of ~30 kpc (115), 383 sources are detected. Cross-correlation with Spitler et al.'s catalog of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-ray sources in GCs, presumably low-mass X-ray binaries (LMXBs). Metal-rich GCs are found to have a higher probability of hosting ...


Mid-Infrared Spectroscopy Of Candidate Active Galactic Nuclei-Dominated Submillimeter Galaxies, K Coppin, A Pope, K Menendez-Delmestre, DM Alexander, JS Dunlop, E Egami, J Gabor, E Ibar, RJ Ivison, JE Austermann, AW Blain, SC Chapman, DL Clements, L Dunne, S Dye, D Farrah, DH Hughes, AMJ Mortier, MJ Page, M Rowan-Robinson, D Scott, C Simpson, I Smail, AM Swinbank, M Vaccari, Min Yun 2010 University of Massachusetts - Amherst

Mid-Infrared Spectroscopy Of Candidate Active Galactic Nuclei-Dominated Submillimeter Galaxies, K Coppin, A Pope, K Menendez-Delmestre, Dm Alexander, Js Dunlop, E Egami, J Gabor, E Ibar, Rj Ivison, Je Austermann, Aw Blain, Sc Chapman, Dl Clements, L Dunne, S Dye, D Farrah, Dh Hughes, Amj Mortier, Mj Page, M Rowan-Robinson, D Scott, C Simpson, I Smail, Am Swinbank, M Vaccari, Min Yun

Astronomy Department Faculty Publication Series

Spitzer spectroscopy has revealed that 80% of submm galaxies (SMGs) are starburst (SB)-dominated in the mid-infrared. Here we focus on the remaining 20% that show signs of harboring powerful active galactic nuclei (AGNs). We have obtained Spitzer-InfraRed Spectrograph spectroscopy of a sample of eight SMGs that are candidates for harboring powerful AGNs on the basis of IRAC color selection (S 8 μm/S 4.5 μm>2, i.e., likely power-law mid-infrared spectral energy distributions). SMGs with an AGN dominating (50%) their mid-infrared emission could represent the "missing link" sources in an evolutionary sequence involving a major merger ...


Molecular And Atomic Gas In The Local Group Galaxy M 33, Gratier, Braine, Rodriguez-Fernandez, Schuster, Kramer, Xilouris, Tabatabaei, Henkel, Corbelli, Israel, van der Werf, D Calzetti 2010 University of Massachusetts Amherst

Molecular And Atomic Gas In The Local Group Galaxy M 33, Gratier, Braine, Rodriguez-Fernandez, Schuster, Kramer, Xilouris, Tabatabaei, Henkel, Corbelli, Israel, Van Der Werf, D Calzetti

Astronomy Department Faculty Publication Series

We present high-resolution large-scale observations of the molecular and atomic gas in the Local Group galaxy M 33. The observations were carried out using the HEterodyne Receiver Array (HERA) at the 30 m IRAM telescope in the CO(2–1) line, achieving a resolution of 12″ × 2.6 km s-1, enabling individual giant molecular clouds (GMCs) to be resolved. The observed region is 650 square arcminutes mainly along the major axis and out to a radius of 8.5 kpc, and covers entirely the 2′ × 40′ radial strip observed with the HIFI and PACS Spectrometers as part of the HERM33ES ...


A High-Resolution Line Survey Of Irc +10216 With Herschel/Hifi *,** First Results: Detection Of Warm Silicon Dicarbide (Sic), J Cernicharo, LBFM Waters, L Decin, P Encrenaz, AGGM Tielens, M Agundez, E DeBeck, HSP Muller, JR Goicoechea, MJ Barlow, A Benz, N Crimier, F Daniel, AM DiGiorgio, M Fich, T Gaier, P Garcia-Lario, A deKoter, T Khouri, R Liseau, R Lombaert, NR Erickson, JR Pardo, JC Pearson, R Shipman, C Sanchez Contreras, D Teyssier 2010 University of Massachusetts - Amherst

A High-Resolution Line Survey Of Irc +10216 With Herschel/Hifi *,** First Results: Detection Of Warm Silicon Dicarbide (Sic), J Cernicharo, Lbfm Waters, L Decin, P Encrenaz, Aggm Tielens, M Agundez, E Debeck, Hsp Muller, Jr Goicoechea, Mj Barlow, A Benz, N Crimier, F Daniel, Am Digiorgio, M Fich, T Gaier, P Garcia-Lario, A Dekoter, T Khouri, R Liseau, R Lombaert, Nr Erickson, Jr Pardo, Jc Pearson, R Shipman, C Sanchez Contreras, D Teyssier

Astronomy Department Faculty Publication Series

We present the first results of a high-spectral-resolution survey of the carbon-rich evolved star IRC+10216 that was carried out with the HIFI spectrometer onboard Herschel. This survey covers all HIFI bands, with a spectral range from 488 to 1901 GHz. In this letter we focus on the band-1b spectrum, in a spectral range 554.5–636.5 GHz, where we identified 130 spectral features with intensities above 0.03 K and a signal-to-noise ratio >5. Detected lines arise from HCN, SiO, SiS, CS, CO, metal-bearing species and, surprisingly, silicon dicarbide (SiC2). We identified 55 SiC2 transitions involving ...


A Spitzer View Of Star Formation In The Cygnus X North Complex, I. M. Beerer, X. P. Koenig, J. L. Hora, R. A. Gutermuth 2010 University of Massachusetts - Amherst

A Spitzer View Of Star Formation In The Cygnus X North Complex, I. M. Beerer, X. P. Koenig, J. L. Hora, R. A. Gutermuth

Astronomy Department Faculty Publication Series

We present new images and photometry of the massive star-forming complex Cygnus X obtained with the Infrared Array Camera (IRAC) and the Multiband Imaging Photometer for Spitzer (MIPS) on board the Spitzer Space Telescope. A combination of IRAC, MIPS, UKIRT Deep Infrared Sky Survey, and Two Micron All Sky Survey data are used to identify and classify young stellar objects (YSOs). Of the 8231 sources detected exhibiting infrared excess in Cygnus X North, 670 are classified as class I and 7249 are classified as class II. Using spectra from the FAST Spectrograph at the Fred L. Whipple Observatory and Hectospec ...


Science Drivers And Requirements For An Advanced Technology Large Aperture Space Telescope (Atlast): Implications For Technology Development And Synergies With Other Future Facilities, M Postman, T Brown, K Sembach, M Giavalisco, W Traub, K Stapelfeldt, D Calzetti 2010 University of Massachusetts - Amherst

Science Drivers And Requirements For An Advanced Technology Large Aperture Space Telescope (Atlast): Implications For Technology Development And Synergies With Other Future Facilities, M Postman, T Brown, K Sembach, M Giavalisco, W Traub, K Stapelfeldt, D Calzetti

Astronomy Department Faculty Publication Series

The Advanced Technology Large-Aperture Space Telescope (ATLAST) is a concept for an 8-meter to 16-meter UVOIR space observatory for launch in the 2025-2030 era. ATLAST will allow astronomers to answer fundamental questions at the forefront of modern astronphysics, including "Is there life elsewhere in the Galaxy?" We present a range of science drivers that define the main performance requirements for ATLAST (8 to 16 milliarcsec angular resolution, diffraction limited imaging at 0.5 μm wavelength, minimum collecting area of 45 square meters, high sensitivity to light wavelengths from 0.1 μm to 2.4 μm, high stability in wavefront sensing ...


An Investigation Of The Dust Content In The Galaxy Pair Ngc 1512/1510 From Near-Infrared To Millimeter Wavelengths, GL Liu, D Calzetti, Min Yun, GW Wilson, BT Draine, K Scott, J Austermann, T Perera, D Hughes, I Aretxaga, K Kohno, R Kawabe, H Ezawa 2010 University of Massachusetts - Amherst

An Investigation Of The Dust Content In The Galaxy Pair Ngc 1512/1510 From Near-Infrared To Millimeter Wavelengths, Gl Liu, D Calzetti, Min Yun, Gw Wilson, Bt Draine, K Scott, J Austermann, T Perera, D Hughes, I Aretxaga, K Kohno, R Kawabe, H Ezawa

Astronomy Department Faculty Publication Series

We combine new ASTE/AzTEC 1.1 mm maps of the galaxy pair NGC 1512/1510 with archival Spitzer IRAC and MIPS images covering the wavelength range 3.6-160 μm from the SINGS project. The availability of the 1.1 mm map enables us to measure the long-wavelength tail of the dust emission in each galaxy, and in sub-galactic regions in NGC 1512, and to derive accurate dust masses. The two galaxies form a pair consisting of a large, high-metallicity spiral (NGC 1512) and a low-metallicity, blue compact dwarf (NGC 1510), which we use to compare similarities and contrast differences ...


Strong Ch+ J = 1–0 Emission And Absorption In Dr21*, E Falgarone, V Ossenkopf, M Gerin, P Lesaffre, B Godard, J Pearson, S Cabrit, Ch Joblin, AO Benz, F Boulanger, A Fuente, R Gusten, A Harris, T Klein, C Kramer, S Lord, P Martain, J Martin-Pintado, D Neufeld, TG Phillips, M Rollig, R Simon, J Stutzki, F van der Tak, D Teyssier, H Yorke, NR Erickson, M Fich, W Jellema, A Marston, C Risacher, M Salez, F Schmulling 2010 University of Massachusetts - Amherst

Strong Ch+ J = 1–0 Emission And Absorption In Dr21*, E Falgarone, V Ossenkopf, M Gerin, P Lesaffre, B Godard, J Pearson, S Cabrit, Ch Joblin, Ao Benz, F Boulanger, A Fuente, R Gusten, A Harris, T Klein, C Kramer, S Lord, P Martain, J Martin-Pintado, D Neufeld, Tg Phillips, M Rollig, R Simon, J Stutzki, F Van Der Tak, D Teyssier, H Yorke, Nr Erickson, M Fich, W Jellema, A Marston, C Risacher, M Salez, F Schmulling

Astronomy Department Faculty Publication Series

We report the first detection of the ground-state rotational transition of the methylidyne cation CH+ towards the massive star-forming region DR 21 with the HIFI instrument onboard the Herschel satellite. The line profile exhibits a broad emission line, in addition to two deep and broad absorption features associated with the DR 21 molecular ridge and foreground gas. These observations allow us to determine a 12CH+J = 1–0 line frequency of ν = 835 137 ± 3 MHz, in good agreement with a recent experimental determination. We estimate the CH+ column density to be a few 1013 cm-2 in ...


Discovery Of A Luminous Blue Variable With An Ejection Nebula Near The Quintuplet Cluster, JC Mauerhan, MR Morris, A Cotera, H Dong, QD Wang, SR Stolovy, C Lang, IS Glass 2010 University of Massachusetts - Amherst

Discovery Of A Luminous Blue Variable With An Ejection Nebula Near The Quintuplet Cluster, Jc Mauerhan, Mr Morris, A Cotera, H Dong, Qd Wang, Sr Stolovy, C Lang, Is Glass

Astronomy Department Faculty Publication Series

We report on the discovery of a luminous blue variable (LBV) lying 7 pc in projection from the Quintuplet cluster. This source, which we call LBV G0.120 – 0.048, was selected for spectroscopy owing to its detection as a strong source of Paschen-α (Pα) excess in a recent narrowband imaging survey of the Galactic center region with the Hubble Space Telescope/Near-Infrared Camera and Multi-Object Spectrometer. The K-band spectrum is similar to that of the Pistol Star and other known LBVs. The new LBV was previously cataloged as a photometric variable star, exhibiting brightness fluctuations of up to ...


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