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Probing Outflows In Z = 1~2 Galaxies Through Fe Ii/Fe Ii Multiplets, Yuping Tang, Mauro Giavalisco, Yicheng Guo, Jaron Kurk
Probing Outflows In Z = 1~2 Galaxies Through Fe Ii/Fe Ii Multiplets, Yuping Tang, Mauro Giavalisco, Yicheng Guo, Jaron Kurk
Mauro Giavalisco
We report on a study of the 2300 − 2600°A Fe II/Fe II∗ multiplets in the rest–UV spectra of star forming galaxies at 1.0 < z < 2.6 as probes of galactic–scale outflows. We extracted a mass–limited sample of 97 galaxies at z _ 1.0 − 2.6 from ultra–deep spectra obtained during the GMASS spetroscopic survey in the GOODS South field with the VLT and FORS2. We obtain robust measures of the rest equivalent width of the Fe II absorption lines down to a limit of Wr > 1.5°A and of the Fe II∗ emission lines to Wr > 0.5°A. Whenever we can measure the systemic redshift of the galaxies from the [O II] emission line, we find that both the Fe II and Mg II absorption lines are blueshifted, indicative that both species trace gaseous outflows. We also find, however, that the Fe II gas has generally lower outflow velocity relative to that of Mg II. We investigate the variation of Fe II line …
Molecular Gas Content Of Hi Monsters And Implications To Cold Gas Content Evolution In Galaxies, Cheoljong Lee, Aeree Chung, Min S. Yun, Ryan Cybulski, Gopal Narayanan, N. Erickson
Molecular Gas Content Of Hi Monsters And Implications To Cold Gas Content Evolution In Galaxies, Cheoljong Lee, Aeree Chung, Min S. Yun, Ryan Cybulski, Gopal Narayanan, N. Erickson
Gopal Narayanan
No abstract provided.
The Neutral Hydrogen Content Of Galaxies In Cosmological Hydrodynamic Simulations, Romeel Dave, Neal S. Katz, Benjamin D. Oppenheimer, Juna A. Kollmeier, David H. Weinberg
The Neutral Hydrogen Content Of Galaxies In Cosmological Hydrodynamic Simulations, Romeel Dave, Neal S. Katz, Benjamin D. Oppenheimer, Juna A. Kollmeier, David H. Weinberg
Neal S. Katz
We examine the global H I properties of galaxies in quarter billion particle cosmological simulations using GADGET-2, focusing on how galactic outflows impact H I content. We consider four outflow models, including a new one (ezw) motivated by recent interstellar medium simulations in which the wind speed and mass loading factor scale as expected for momentum-driven outflows for larger galaxies and energy-driven outflows for dwarfs (σ < 75 km s−1). To obtain predicted H I masses, we employ a simple but effective local correction for particle self-shielding and an observationally constrained transition from neutral to molecular hydrogen. Our ezw simulation produces an H I mass function whose faint-end slope of −1.3 agrees well with observations from the Arecibo Fast Legacy ALFA survey; other models agree less well. Satellite galaxies have a bimodal distribution in H I fraction versus halo mass, with smaller satellites and/or those in larger haloes more often being H I deficient. At a given stellar mass, H I content correlates with the star formation rate and inversely correlates with metallicity, as expected if driven by stochasticity in the accretion rate. To higher redshifts, massive H I galaxies disappear and the mass function steepens. The global cosmic H I density conspires to remain fairly constant from z ∼ 5 → 0, but the relative contribution from smaller galaxies increases with redshift.
Resolving The Far-Ir Line Deficit: Photoelectric Heating And Far-Ir Line Cooling In Ngc 1097 And Ngc 4559, Kevin V. Croxall, J. D. Smith, M. G. Wolfire, H. Roussel, K. M. Sandstrom, B. T. Draine, G. Aniano, D. A. Dale, L. Armus, P. Beirão, G. Helou, A. D. Bolatto, P. N. Appleton, B. R. Brandl, Daniela Calzetti, A. F. Crocker, M. Galametz, B. A. Groves, C.-N. Hao, L. K. Hunt, B. D. Johnson, R, C, Kennicutt, J. Koda, O. Krause, Y. Li, S. E. Meidt, E. J. Murphy, N. Rahman, H.-W. Rix, M. Sauvage, E. Schinnerer, F. Walter, C. D. Wilson
Resolving The Far-Ir Line Deficit: Photoelectric Heating And Far-Ir Line Cooling In Ngc 1097 And Ngc 4559, Kevin V. Croxall, J. D. Smith, M. G. Wolfire, H. Roussel, K. M. Sandstrom, B. T. Draine, G. Aniano, D. A. Dale, L. Armus, P. Beirão, G. Helou, A. D. Bolatto, P. N. Appleton, B. R. Brandl, Daniela Calzetti, A. F. Crocker, M. Galametz, B. A. Groves, C.-N. Hao, L. K. Hunt, B. D. Johnson, R, C, Kennicutt, J. Koda, O. Krause, Y. Li, S. E. Meidt, E. J. Murphy, N. Rahman, H.-W. Rix, M. Sauvage, E. Schinnerer, F. Walter, C. D. Wilson
Daniela Calzetti
The physical state of interstellar gas and dust is dependent on the processes which heat and cool this medium. To probe heating and cooling of the ISM over a large range of infrared surface brightness, on sub-kiloparsec scales, we employ line maps of [C \ii] 158 $\mu$m, [O \one] 63 $\mu$m, and [N \ii] 122 $\mu$m in NGC 1097 and NGC 4559, obtained with the PACS spectrometer onboard {\it Herschel}. We matched new observations to existing Spitzer-IRS data that trace the total emission of polycyclic aromatic hydrocarbons (PAHs). We confirm at small scales in these galaxies that the canonical measure …
Star Formation Laws: The Effects Of Gas Cloud Sampling, Daniela Calzetti, G. Liu, J. Koda
Star Formation Laws: The Effects Of Gas Cloud Sampling, Daniela Calzetti, G. Liu, J. Koda
Daniela Calzetti
Recent observational results indicate that the functional shape of the spatially-resolved star formation-molecular gas density relation depends on the spatial scale considered. These results may indicate a fundamental role of sampling effects on scales that are typically only a few times larger than those of the largest molecular clouds. To investigate the impact of this effect, we construct simple models for the distribution of molecular clouds in a typical star-forming spiral galaxy, and, assuming a power-law relation between SFR and cloud mass, explore a range of input parameters. We confirm that the slope and the scatter of the simulated SFR-molecular …
Kingfish -- Key Insights On Nearby Galaxies: A Far-Infrared Survey With Herschel: Survey Description And Image Atlas, R. C. Kennicutt, Daniela Calzetti, G. Aniano, P. Appleton, L. Armus, P. Beirão, A. D. Bolatto, B. Brandl, A. Crocker, K. Croxall, D. A. Dale, J. Donovan Meyer, B. T. Draine, C. W. Engelbracht, M. Galametz, K. D. Gordon, B. Groves, C.-N. Hao, G. Helou, J. Hinz, L. K. Hunt, B. Johnson, J. Koda, O. Krause, A. K. Leroy, Y. Li, S. Meidt, E. Montiel, E. J. Murphy, N. Rahman, H.-W. Rix, H. Roussel, K. Sandstrom, M. Sauvage, E. Schinnerer, K. Skibba, J. D. T. Smith, S. Srinivasan, L. Virgroux, F. Walter, C. D. Wilson, M. Wolfire, S. Zibetti
Kingfish -- Key Insights On Nearby Galaxies: A Far-Infrared Survey With Herschel: Survey Description And Image Atlas, R. C. Kennicutt, Daniela Calzetti, G. Aniano, P. Appleton, L. Armus, P. Beirão, A. D. Bolatto, B. Brandl, A. Crocker, K. Croxall, D. A. Dale, J. Donovan Meyer, B. T. Draine, C. W. Engelbracht, M. Galametz, K. D. Gordon, B. Groves, C.-N. Hao, G. Helou, J. Hinz, L. K. Hunt, B. Johnson, J. Koda, O. Krause, A. K. Leroy, Y. Li, S. Meidt, E. Montiel, E. J. Murphy, N. Rahman, H.-W. Rix, H. Roussel, K. Sandstrom, M. Sauvage, E. Schinnerer, K. Skibba, J. D. T. Smith, S. Srinivasan, L. Virgroux, F. Walter, C. D. Wilson, M. Wolfire, S. Zibetti
Daniela Calzetti
The KINGFISH project (Key Insights on Nearby Galaxies: a Far-Infrared Survey with Herschel) is an imaging and spectroscopic survey of 61 nearby (d < 30 Mpc) galaxies, chosen to cover a wide range of galaxy properties and local interstellar medium (ISM) environments found in the nearby Universe. Its broad goals are to characterize the ISM of present-day galaxies, the heating and cooling of their gaseous and dust components, and to better understand the physical processes linking star formation and the ISM. KINGFISH is a direct descendant of the Spitzer Infrared Nearby Galaxies Survey (SINGS), which produced complete Spitzer imaging and spectroscopic mapping and a comprehensive set of multi-wavelength ancillary observations for the sample. The Herschel imaging consists of complete maps for the galaxies at 70, 100, 160, 250, 350, and 500 microns. The spectal line imaging of the principal atomic ISM cooling lines ([OI]63um, [OIII]88um, [NII]122,205um, and [CII]158um) covers the subregions in the centers and disks that already have been mapped in the mid-infrared with Spitzer. The KINGFISH and SINGS multi-wavelength datasets combined provide panchromatic mapping of the galaxies sufficient to resolve individual star-forming regions, and tracing the important heating and cooling channels of the ISM, across a wide range of local extragalactic ISM environments. This paper summarizes the scientific strategy for KINGFISH, the properties of the galaxy sample, the observing strategy, and data processing and products. It also presents a combined Spitzer and Herschel image atlas for the KINGFISH galaxies, covering the wavelength range 3.6 -- 500 microns. All imaging and spectroscopy data products will be released to the Herschel user generated product archives.
Dust-Corrected Star Formation Rates Of Galaxies. Ii. Combinations Of Ultraviolet And Infrared Tracers, Cai-Na Hao, C. Kennicutt Kr., Benjamin D. Johnson, Daniela Calzetti, Daniel A. Dale, John Moustakas
Dust-Corrected Star Formation Rates Of Galaxies. Ii. Combinations Of Ultraviolet And Infrared Tracers, Cai-Na Hao, C. Kennicutt Kr., Benjamin D. Johnson, Daniela Calzetti, Daniel A. Dale, John Moustakas
Daniela Calzetti
We present new calibrations of far-ultraviolet (FUV) attenuation as derived from the total infrared to FUV luminosity ratio (IRX) and the FUV-NUV color. We find that the IRX-corrected FUV luminosities are tightly and linearly correlated with the attenuation-corrected H\alpha\ luminosities (as measured from the Balmer decrement), with a rms scatter of $\pm 0.09$ dex. The ratios of these attenuation-corrected FUV to H\alpha\ luminosities are consistent with evolutionary synthesis model predictions, assuming a constant star formation rate over 100 Myr, solar metallicity and either a Salpeter or a Kroupa IMF with lower and upper mass limits of 0.1 and 100\msun. The …
Herschel Far-Infrared And Sub-Millimeter Photometry For The Kingfish Sample Of Nearby Galaxies, D. A. Dale, G. Aniano, C. W. Engelbracht, J. L. Hinz, O. Krause, E. J. Montiel, H. Roussel, P. N. Appleton, L. Armus, P. Beirão, A. D. Bolatto, B. R. Brandl, Daniela Calzetti, A. F. Crocker, K. F. Croxall, B. T. Draine, M. Galametz, K. D. Gordon, B. A. Groves, C.-N. Hao, G. Helou, L. K. Hunt, B. D. Johnson, R. C. Kennicutt, J. Koda, A. K. Leroy, Y. Li, S. E. Meidt, A. E. Miller, E. J. Murphy, N. Rahman, H.-W. Rix, K. M. Sandstrom, M. Sauvage, E. Schinnerer, R. A. Skibba, J.-D. T. Smith, F. S. Tabatabaei, F. Walter, C. D. Wilson, M. G. Wolfire, S. Zibetti
Herschel Far-Infrared And Sub-Millimeter Photometry For The Kingfish Sample Of Nearby Galaxies, D. A. Dale, G. Aniano, C. W. Engelbracht, J. L. Hinz, O. Krause, E. J. Montiel, H. Roussel, P. N. Appleton, L. Armus, P. Beirão, A. D. Bolatto, B. R. Brandl, Daniela Calzetti, A. F. Crocker, K. F. Croxall, B. T. Draine, M. Galametz, K. D. Gordon, B. A. Groves, C.-N. Hao, G. Helou, L. K. Hunt, B. D. Johnson, R. C. Kennicutt, J. Koda, A. K. Leroy, Y. Li, S. E. Meidt, A. E. Miller, E. J. Murphy, N. Rahman, H.-W. Rix, K. M. Sandstrom, M. Sauvage, E. Schinnerer, R. A. Skibba, J.-D. T. Smith, F. S. Tabatabaei, F. Walter, C. D. Wilson, M. G. Wolfire, S. Zibetti
Daniela Calzetti
New far-infrared and sub-millimeter photometry from the Herschel Space Observatory is presented for 61 nearby galaxies from the Key Insights on Nearby Galaxies: A Far-Infrared Survey with Herschel (KINGFISH) sample. The spatially-integrated fluxes are largely consistent with expectations based on Spitzer far-infrared photometry and extrapolations to longer wavelengths using popular dust emission models. Dwarf irregular galaxies are notable exceptions, as already noted by other authors, as their 500um emission shows evidence for a sub-millimeter excess. In addition, the fraction of dust heating attributed to intense radiation fields associated with photo-dissociation regions is found to be (21+/-4)% larger when Herschel data …
The Emission By Dust And Stars Of Nearby Galaxies In The Herschel Kingfish Survey, Ramin A. Skibba, Charles W. Engelbracht, Daniel Dale, Joannah Hinz, Stefano Zibetti, Alison Crocker, Brent Groves, Leslie Hunt, Benjamin D. Johnson, Sharon Meidt, Eric J. Murphy, Philip Appleton, Lee Armus, Alberto Bolatto, Bernhard Brandl, Daniela Calzetti, Kevin Croxall, Maud Galametz, Karl. D. Gordon, Robert C. Kennicutt, Jin Koda, Oliver Krause, Edward Montiel, Hans-Walter Rix, Hélène Roussel, Karin Sandstrom, Marc Sauvage, Eva Schinnerer, J. D. Smith, Fabian Walter, Christine D. Wilson, Mark Wolfire
The Emission By Dust And Stars Of Nearby Galaxies In The Herschel Kingfish Survey, Ramin A. Skibba, Charles W. Engelbracht, Daniel Dale, Joannah Hinz, Stefano Zibetti, Alison Crocker, Brent Groves, Leslie Hunt, Benjamin D. Johnson, Sharon Meidt, Eric J. Murphy, Philip Appleton, Lee Armus, Alberto Bolatto, Bernhard Brandl, Daniela Calzetti, Kevin Croxall, Maud Galametz, Karl. D. Gordon, Robert C. Kennicutt, Jin Koda, Oliver Krause, Edward Montiel, Hans-Walter Rix, Hélène Roussel, Karin Sandstrom, Marc Sauvage, Eva Schinnerer, J. D. Smith, Fabian Walter, Christine D. Wilson, Mark Wolfire
Daniela Calzetti
Using new far-infrared imaging from the Herschel Space Observatory with ancillary data from ultraviolet to submillimeter wavelengths, we estimate the total emission from dust and stars of 62 nearby galaxies in the KINGFISH survey in a way that is as empirical and model-independent as possible. We collect and exploit these data in order to measure from the spectral energy distributions (SEDs) precisely how much stellar radiation is intercepted and re-radiated by dust, and how this quantity varies with galaxy properties. By including SPIRE data, we are more sensitive to emission from cold dust grains than previous analyses at shorter wavelengths, …
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
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
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
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
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
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 …
A Systematic Study Of The Stellar Populations And Ism In Galaxies Out To The Virgo Cluster: Near Field Cosmology Within A Representative Slice Of The Local Universe, Rolf A. Jansen, Paul Scowen, Matthew Beasley, John Gallagher, Robert O'Connell, Daniela Calzetti, Sally Oey, Rogier Windhorst, Robert Woodruff
A Systematic Study Of The Stellar Populations And Ism In Galaxies Out To The Virgo Cluster: Near Field Cosmology Within A Representative Slice Of The Local Universe, Rolf A. Jansen, Paul Scowen, Matthew Beasley, John Gallagher, Robert O'Connell, Daniela Calzetti, Sally Oey, Rogier Windhorst, Robert Woodruff
Astronomy Department Faculty Publication Series
We present a compelling case for a systematic and comprehensive study of the resolved and unresolved stellar populations, ISM, and immediate environments of galaxies throughout the local volume, defined here as D < 20 Mpc. This volume is our cosmic backyard and the smallest volume that encompasses environments as different as the Virgo, Ursa Major, Fornax and (perhaps) Eridanus clusters of galaxies, a large number and variety of galaxy groups, and several cosmic void regions. In each galaxy, through a pan-chromatic (160--1100nm) set of broad-band and diagnostic narrow-band filters, ISM structures and individual luminous stars to >~1 mag below the TRGB should be resolved on scales of <5 pc (at D <~ 20 Mpc, lambda ~ 800nm, for mu_I >~ 24 mag/arcsec^2 and m_{I,TRGB} <~ 27.5 mag). Resolved and unresolved stellar populations would be analyzed through color-magnitude and color-color diagram fitting and population synthesis modeling of multi-band colors and would yield physical properties such as spatially resolved star formation histories. The ISM within and around each galaxy would be analyzed using key narrow-band filters that distinguish photospheric from shock heating and provide information on the metallicity of the gas. Such a study would finally allow unraveling the global and spatially resolved star formation histories of galaxies, their assembly, satellite systems, and the dependences thereof on local and global environment within a truly representative cosmic volume. The proposed study is not feasible with current instrumentation but argues for a wide-field (>~250 arcmin^2), high-resolution (<~0.020"--0.065" [300--1000nm]), ultraviolet--near-infrared imaging facility on a 4m-class space-based observatory.
Dust-Corrected Star Formation Rates Of Galaxies. I. Combinations Of H Alpha And Infrared Tracers, Rc Kennicutt, Cn Hao, D Calzetti, J Moustakas, Da Dale, G Bendo, Cw Engelbracht, Bd Johnson, Jc Lee
Dust-Corrected Star Formation Rates Of Galaxies. I. Combinations Of H Alpha And Infrared Tracers, Rc Kennicutt, Cn Hao, D Calzetti, J Moustakas, Da Dale, G Bendo, Cw Engelbracht, Bd Johnson, Jc Lee
Astronomy Department Faculty Publication Series
We combine Hα emission-line and infrared (IR) continuum measurements of two samples of nearby galaxies to derive dust attenuation-corrected star formation rates (SFRs). We use a simple energy balance based method that has been applied previously to H II regions in the Spitzer Infrared Nearby Galaxies Survey, and extend the methodology to integrated measurements of galaxies. We find that our composite Hα + IR based SFRs are in excellent agreement with attenuation-corrected SFRs derived from integrated spectrophotometry, over the full range of SFRs (0.01-80 M sun yr-1) and attenuations (0-2.5 mag) studied. We find that the combination of Hα and …
Feedback From Galactic Stellar Bulges And Hot Gaseous Haloes Of Galaxies, Sk Tang, Qd Wang, Y Lu, Hj Mo
Feedback From Galactic Stellar Bulges And Hot Gaseous Haloes Of Galaxies, Sk Tang, Qd Wang, Y Lu, Hj Mo
Astronomy Department Faculty Publication Series
We demonstrate that the feedback from stellar bulges can, in principle, play an essential role in shaping the halo gas of galaxies with substantial bulge components by conducting 1D hydrodynamical simulations. The feedback model we consider consists of two distinct phases: (i) an early starburst during the bulge formation and (ii) a subsequent long-lasting mass and energy injection from stellar winds of low-mass stars and Type Ia supernovae. An energetic outward blastwave is initiated by the starburst and maintained and enhanced by the long-lasting stellar feedback. For a Milky Way like galactic bulge, this blastwave heats up the circum-galactic medium …
(Co)-C-12(J=1-0) On-The-Fly Mapping Survey Of The Virgo Cluster Spirals. I. Data And Atlas, E.J. Chung, M.-H. Rhee, H. Kim, Min S. Yun, M. Heyer, J. S. Young
(Co)-C-12(J=1-0) On-The-Fly Mapping Survey Of The Virgo Cluster Spirals. I. Data And Atlas, E.J. Chung, M.-H. Rhee, H. Kim, Min S. Yun, M. Heyer, J. S. Young
Astronomy Department Faculty Publication Series
We have performed an On-The-Fly (OTF) mapping survey of 12CO(J = 1-0) emission in 28 Virgo cluster spiral galaxies using the Five College Radio Astronomy Observatory (FCRAO) 14 m telescope. This survey aims to characterize the CO distribution, kinematics, and luminosity of a large sample of galaxies covering the full extents of stellar disks, rather than sampling only the inner disks or the major axis as was done by many previous single dish and interferometric CO surveys. CO emission is detected in 20 galaxies among the 28 Virgo spirals observed. An atlas consisting of global measures, radial measures, …
Spectra Of Nearby Galaxies Measured With A New Very Broadband Receiver, Gopal Narayanan, Ronald L. Snell, Nr Erickson, Aeree Chung, Mark H. Heyer, Min Yun, William M. Irvine
Spectra Of Nearby Galaxies Measured With A New Very Broadband Receiver, Gopal Narayanan, Ronald L. Snell, Nr Erickson, Aeree Chung, Mark H. Heyer, Min Yun, William M. Irvine
Astronomy Department Faculty Publication Series
Three-millimeter-wavelength spectra of a number of nearby galaxies have been obtained at the Five College Radio Astronomy Observatory (FCRAO) using a new, very broadband receiver. This instrument, which we call the Redshift Search Receiver, has an instantaneous bandwidth of 36 GHz and operates from 74 to 110.5 GHz. The receiver has been built at UMass/FCRAO to be part of the initial instrumentation for the Large Millimeter Telescope (LMT) and is intended primarily for determination of the redshift of distant, dust-obscured galaxies. It is being tested on the FCRAO 14 m by measuring the 3 mm spectra of a number of …
Spectra Of Nearby Galaxies Measured With A New Very Broadband Receiver, Gopal Narayanan, Ronald L. Snell, Neal R. Erickson, Aeree Chung, Mark H. Heyer, Min Yun, William M. Irvine
Spectra Of Nearby Galaxies Measured With A New Very Broadband Receiver, Gopal Narayanan, Ronald L. Snell, Neal R. Erickson, Aeree Chung, Mark H. Heyer, Min Yun, William M. Irvine
Gopal Narayanan
Three-millimeter-wavelength spectra of a number of nearby galaxies have been obtained at the Five College Radio Astronomy Observatory (FCRAO) using a new, very broadband receiver. This instrument, which we call the Redshift Search Receiver, has an instantaneous bandwidth of 36 GHz and operates from 74 to 110.5 GHz. The receiver has been built at UMass/FCRAO to be part of the initial instrumentation for the Large Millimeter Telescope (LMT) and is intended primarily for determination of the redshift of distant, dust-obscured galaxies. It is being tested on the FCRAO 14 m by measuring the 3 mm spectra of a number of …
Neutral Hydrogen Distribution In Merging Galaxies: Differences Between Stellar And Gaseous Tidal Morphologies, J E. Hibbard, W D. Vacca, Min S. Yun
Neutral Hydrogen Distribution In Merging Galaxies: Differences Between Stellar And Gaseous Tidal Morphologies, J E. Hibbard, W D. Vacca, Min S. Yun
Min S. Yun
As part of several H I synthesis-mapping studies of merging galaxies, we have mapped the tidal gas in the three disk-disk merger systems Arp 157 (NGC 520), Arp 220, and Arp 299 (NGC 3690). These systems differ from the majority of the mergers mapped in H I in that their stellar and gaseous tidal features do not coincide. In particular, they exhibit large stellar tidal features with little if any accompanying neutral gas and large gas-rich tidal features with little if any accompanying starlight. On smaller scales, there are striking anticorrelations in which the gaseous and stellar tidal features appear …
Co Distribution And Kinematics Along The Bar In The Strongly Barred Spiral Ngc 7479, S Laine, J D P Kenny, Min S. Yun, S T. Gottesman
Co Distribution And Kinematics Along The Bar In The Strongly Barred Spiral Ngc 7479, S Laine, J D P Kenny, Min S. Yun, S T. Gottesman
Min S. Yun
We report on the 2farcs5 (400 pc) resolution CO (J=1→0) observations covering the whole length of the bar in the strongly barred late-type spiral galaxy NGC 7479. CO emission is detected only along a dust lane that traverses the whole length of the bar, including the nucleus. The emission is strongest in the nucleus. The distribution of emission is clumpy along the bar outside the nucleus and consists of gas complexes that are unlikely to be gravitationally bound. The CO kinematics within the bar consist of two separate components. A kinematically distinct circumnuclear disk, <500 pc in diameter, is undergoing predominantly circular motion with a maximum rotational velocity of 245 km s-1 at a radius of 1'' (160 pc). The CO-emitting gas in the bar outside the circumnuclear disk has substantial noncircular motions that are consistent with a large radial velocity component, directed inward. The CO emission has a large velocity gradient across the bar dust lane, ranging from 0.5 to 1.9 km s-1 pc-1 after correcting for inclination, and the projected velocity change across the dust lane is as high as 200 km s-1. This sharp velocity gradient is consistent with a shock front at the location of the bar dust lane. A comparison of Hα and CO kinematics across the dust lane shows that, although the Hα emission is often observed both upstream and downstream from the dust lane, the CO emission is observed only where the velocity gradient is large. We also compare the observations with hydrodynamic models and discuss star formation along the bar.
Counterrotating Nuclear Disks In Arp 220, K Sakamoto, N Z. Scoville, Min S. Yun, M Crosas, R Genzel, L J. Tacconi
Counterrotating Nuclear Disks In Arp 220, K Sakamoto, N Z. Scoville, Min S. Yun, M Crosas, R Genzel, L J. Tacconi
Min S. Yun
The ultraluminous infrared galaxy Arp 220 has been observed at 0farcs5 resolution in CO (2-1) and 1 mm continuum using the newly expanded Owens Valley Millimeter Array. The CO and continuum peaks at the double nuclei and the surrounding molecular gas disk are clearly resolved. We find steep velocity gradients across each nucleus (ΔV~500 km s-1 within r=0farcs3) whose directions are not aligned with each other and with that of the outer gas disk. We conclude that the double nuclei have their own gas disks (r~100 pc), are counterrotating with respect to each other, and are embedded in the outer …
Nonlinear Dependence Of Lb On Lfir And Mh2 Among Spiral Galaxies And The Effects Of Tidal Interaction, J Perea, A Del Olmo, L Verdes-Montenegro, Min S. Yun
Nonlinear Dependence Of Lb On Lfir And Mh2 Among Spiral Galaxies And The Effects Of Tidal Interaction, J Perea, A Del Olmo, L Verdes-Montenegro, Min S. Yun
Min S. Yun
Through the study of a carefully selected sample of isolated spiral galaxies, we have established that two important global physical quantities for tracing star-forming activities, LFIR and MH2, have a nonlinear dependence on another commonly cited global quantity, LB. Furthermore, we show that simple power-law relations can effectively describe these nonlinear relations for spiral galaxies spanning 4 orders of magnitude in FIR and MH2, and nearly 3 orders of magnitude in LB. While the existence of a nonlinear dependence of MH2 (assuming a constant CO-to-H2 conversion) and LFIR on optical luminosity (LB) has been previously noted in the literature, an …