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Physical Sciences and Mathematics Commons

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Astrophysics and Astronomy

University of Massachusetts Amherst

Series

2010

Galaxies: ISM

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

An Aromatic Inventory Of The Local Volume, Ar Marble, Cw Engelbracht, L Van Zee, Da Dale, Jdt Smith, Kd Gordon, Y Wu, Jc Lee, Rc Kennicutt, Ed Skillman, Lc Johnson, M Block, D Calzetti, Sa Cohen, H Lee, Md Schuster Jan 2010

An Aromatic Inventory Of The Local Volume, Ar Marble, Cw Engelbracht, L Van Zee, Da Dale, Jdt Smith, Kd Gordon, Y Wu, Jc Lee, Rc Kennicutt, Ed Skillman, Lc Johnson, M Block, D Calzetti, Sa Cohen, H Lee, Md Schuster

Astronomy Department Faculty Publication Series

Using infrared photometry from the Spitzer Space Telescope, we perform the first inventory of aromatic feature emission (also commonly referred to as polycyclic aromatic hydrocarbon emission) for a statistically complete sample of star-forming galaxies in the local volume. The photometric methodology involved is calibrated and demonstrated to recover the aromatic fraction of the Infrared Array Camera 8 μm flux with a standard deviation of 6% for a training set of 40 SINGS galaxies (ranging from stellar to dust dominated) with both suitable mid-infrared Spitzer Infrared Spectrograph spectra and equivalent photometry. A potential factor of 2 improvement could be realized with …


The Calibration Of Monochromatic Far-Infrared Star Formation Rate Indicators, D Calzetti, Sy Wu, S Hong, Rc Kennicutt, Jc Lee, Da Dale, Cw Engelbracht, L Van Zee, Bt Draine, Cn Hao, Kd Gordon, J Moustakas, Ej Murphy, M Regan, A Begum, M Block, J Dalcanton, J Funes, Ag De Paz, B Johnson, S Sakai, E Skillman, F Walter, D Weisz, B Williams, Y Wu Jan 2010

The Calibration Of Monochromatic Far-Infrared Star Formation Rate Indicators, D Calzetti, Sy Wu, S Hong, Rc Kennicutt, Jc Lee, Da Dale, Cw Engelbracht, L Van Zee, Bt Draine, Cn Hao, Kd Gordon, J Moustakas, Ej Murphy, M Regan, A Begum, M Block, J Dalcanton, J Funes, Ag De Paz, B Johnson, S Sakai, E Skillman, F Walter, D Weisz, B Williams, Y Wu

Astronomy Department Faculty Publication Series

Spitzer data at 24, 70, and 160 μm and ground-based Hα images are analyzed for a sample of 189 nearby star-forming and starburst galaxies to investigate whether reliable star formation rate (SFR) indicators can be defined using the monochromatic infrared dust emission centered at 70 and 160 μm. We compare recently published recipes for SFR measures using combinations of the 24 μm and observed Hα luminosities with those using 24 μm luminosity alone. From these comparisons, we derive a reference SFR indicator for use in our analysis. Linear correlations between SFR and the 70 μm and 160 μm luminosity are …


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 Jan 2010

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.


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 Jan 2010

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. Using the models of Draine …


Using 21 Cm Absorption In Small Impact Parameter Galaxy-Quasar Pairs To Probe Low-Redshift Damped And Sub-Damped Ly Alpha Systems, S Borthakur, Tm Tripp, Min Yun, E Momjian, Jd Meiring, Dv Bowen, Dg York Jan 2010

Using 21 Cm Absorption In Small Impact Parameter Galaxy-Quasar Pairs To Probe Low-Redshift Damped And Sub-Damped Ly Alpha Systems, S Borthakur, Tm Tripp, Min Yun, E Momjian, Jd Meiring, Dv Bowen, Dg York

Astronomy Department Faculty Publication Series

To search for low-redshift damped Lyα (DLA) and sub-DLA quasar absorbers, we have conducted a 21 cm absorption survey of radio-loud quasars at small impact parameters to foreground galaxies selected from the Sloan Digital Sky Survey (SDSS). Here we present the first results from this survey based on observations of SDSS J104257.58+074850.5 (z QSO = 2.66521), a quasar at an angular separation from a foreground galaxy (z gal = 0.03321) of 25 (1.7 kpc in projection). The foreground galaxy is a low-luminosity spiral with on-going star formation (0.004 M yr–1 kpc–2) and a metallicity of …