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Full-Text Articles in Physical Sciences and Mathematics

Delving Deep: A Population Of Extremely Dusty Dwarfs Observed By Jwst, L. Bisigello, G. Gandolfi, A. Grazian, G. Rodighiero, L. Costantin, A. R. Cooray, A. Feltre, C. Gruppioni, N. P. Hathi, Benne W. Holwerda, A. M. Koekemoer, R. A. Lucas, J. A. Newman, P. G. Pérez-González, L. Y. A. Yung, A. De La Vega, P. Arrabal Haro, M. B. Bagley, M. Dickinson, S. L. Finkelstein, J. S. Kartaltepe, C. Papovich, N. Pirzkal, S. Wilkins Aug 2023

Delving Deep: A Population Of Extremely Dusty Dwarfs Observed By Jwst, L. Bisigello, G. Gandolfi, A. Grazian, G. Rodighiero, L. Costantin, A. R. Cooray, A. Feltre, C. Gruppioni, N. P. Hathi, Benne W. Holwerda, A. M. Koekemoer, R. A. Lucas, J. A. Newman, P. G. Pérez-González, L. Y. A. Yung, A. De La Vega, P. Arrabal Haro, M. B. Bagley, M. Dickinson, S. L. Finkelstein, J. S. Kartaltepe, C. Papovich, N. Pirzkal, S. Wilkins

Faculty Scholarship

Aims. We take advantage of the NIRCam photometric observations available as part of the Cosmic Evolution Early Release Science survey (CEERS) to identify and analyse very red sources in an effort to discover very dusty star forming galaxies. Methods. We select red galaxies as objects with a S / N > 3 at 4.4 μm and a S / N < 2 in all JWST and HST filters at λ ≤ 2 μm, which corresponds to [ F 200 W ]−[ F 444 W ]> 1.2 considering CEERS depths. This selection is ideal to identify very dusty ( A V > 1 mag) galaxies with stellar masses between 10 6 and 10 10 M ⊙ at z < 5, more massive dusty galaxies at z = 5 − 18 and galaxies at z > 18 due to the Lyman absorption, independently of their dust …


Dust–Gas Scaling Relations And Oh Abundance In The Galactic Ism, Hiep Nguyen, J. R. Dawson, M. -A. Miville-Deschênes, Ningyu Tang, Di Li, Carl Heiles, Claire E. Murray, Snežana Stanimirović, Steven J. Gibson, N. M. Mcclure-Griffiths, Thomas Troland, L. Bronfman, R. Finger Jul 2018

Dust–Gas Scaling Relations And Oh Abundance In The Galactic Ism, Hiep Nguyen, J. R. Dawson, M. -A. Miville-Deschênes, Ningyu Tang, Di Li, Carl Heiles, Claire E. Murray, Snežana Stanimirović, Steven J. Gibson, N. M. Mcclure-Griffiths, Thomas Troland, L. Bronfman, R. Finger

Physics and Astronomy Faculty Publications

Observations of interstellar dust are often used as a proxy for total gas column density NH. By comparing Planck thermal dust data (Release 1.2) and new dust reddening maps from Pan-STARRS 1 and 2MASS, with accurate (opacity-corrected) H I column densities and newly published OH data from the Arecibo Millennium survey and 21-SPONGE, we confirm linear correlations between dust optical depth τ353, reddening E(BV), and the total proton column density NH in the range (1–30) × 1020 cm−2, along sightlines with no molecular gas detections in emission. …


Herschel Observations Of Edge-On Spirals (Heroes) Iv. Dust Energy Balance Problem, Aleksandr V. Mosenkov, Flor Allaert, Maarten Baes, Simone Bianchi, Peter Camps, Christopher J.R. Clark, Marjorie Decleir, Gert De Geyter, Ilse De Looze, Jacopo Fritz, Gianfranco Gentile, Benne W. Holwerda, Thomas M. Hughes, Fraser Lewis, Matthew W.L. Smith, Joris Verstappen, Sam Verstocken, Sébastien Viaene Jan 2018

Herschel Observations Of Edge-On Spirals (Heroes) Iv. Dust Energy Balance Problem, Aleksandr V. Mosenkov, Flor Allaert, Maarten Baes, Simone Bianchi, Peter Camps, Christopher J.R. Clark, Marjorie Decleir, Gert De Geyter, Ilse De Looze, Jacopo Fritz, Gianfranco Gentile, Benne W. Holwerda, Thomas M. Hughes, Fraser Lewis, Matthew W.L. Smith, Joris Verstappen, Sam Verstocken, Sébastien Viaene

Faculty Scholarship

We present results of the detailed dust energy balance study for the seven large edge-on galaxies in the HEROES sample using three-dimensional (3D) radiative transfer (RT) modelling. Based on available optical and near-infrared (NIR) observations of the HEROES galaxies, we derive the 3D distribution of stars and dust in these galaxies. For the sake of uniformity, we apply the same technique to retrieve galaxy properties for the entire sample: we use a stellar model consisting of a Sérsic bulge and three double-exponential discs (a superthin disc for a young stellar population and thin and thick discs for old populations). For …


On The Time Variation Of Dust Extinction And Gas Absorption For Type Ia Supernovae Observed Through A Nonuniform Interstellar Medium, Xiaosheng Huang, G Aldering, M. Biederman, B. Herger Nov 2017

On The Time Variation Of Dust Extinction And Gas Absorption For Type Ia Supernovae Observed Through A Nonuniform Interstellar Medium, Xiaosheng Huang, G Aldering, M. Biederman, B. Herger

Physics and Astronomy

For Type Ia supernovae (SNe Ia) observed through a nonuniform interstellar medium (ISM) in its host galaxy, we investigate whether the nonuniformity can cause observable time variations in dust extinction and in gas absorption due to the expansion of the SN photosphere with time. We show that, owing to the steep spectral index of the ISM density power spectrum, sizable density fluctuation amplitudes at the length scale of typical ISM structures () will translate to much smaller fluctuations on the scales of an SN photosphere. Therefore, the typical amplitude of time variation due to a nonuniform ISM, of absorption equivalent …


Early Science With The Large Millimeter Telescope: Detection Of Dust Emission In Multiple Images Of A Normal Galaxy At Z > 4 Lensed By A Frontier Fields Cluster, Alexandra Pope, Alfredo Montaña, Andrew Battisti, Marceau Limousin, Danilo Marchesini, Grant W. Wilson, Stacy Alberts, Itziar Aretxaga, Vladimir Avila-Reese, José Ramón Bermejo-Climent, Gabriel Brammer, Hector Bravo-Alfaro, Daniela Calzetti, Ranga-Ram Chary, Ryan Cybulski, Mauro Giavalisco, David Hughes, Erin Kado-Fong, Erica Keller, Allison Kirkpatrick, Ivo Labbe, Daniel Lange-Vagle, James Lowenthal, Eric Murphy, Pascal Oesch, Daniel Rosa Gonzalez, David Sánchez-Argüelles, Heath Shipley, Mauro Stefanon, Olga Vega, Katherine Whitaker, Christina C. Williams, Min Yun, Jorge A. Zavala, Milagros Zeballos Apr 2017

Early Science With The Large Millimeter Telescope: Detection Of Dust Emission In Multiple Images Of A Normal Galaxy At Z > 4 Lensed By A Frontier Fields Cluster, Alexandra Pope, Alfredo Montaña, Andrew Battisti, Marceau Limousin, Danilo Marchesini, Grant W. Wilson, Stacy Alberts, Itziar Aretxaga, Vladimir Avila-Reese, José Ramón Bermejo-Climent, Gabriel Brammer, Hector Bravo-Alfaro, Daniela Calzetti, Ranga-Ram Chary, Ryan Cybulski, Mauro Giavalisco, David Hughes, Erin Kado-Fong, Erica Keller, Allison Kirkpatrick, Ivo Labbe, Daniel Lange-Vagle, James Lowenthal, Eric Murphy, Pascal Oesch, Daniel Rosa Gonzalez, David Sánchez-Argüelles, Heath Shipley, Mauro Stefanon, Olga Vega, Katherine Whitaker, Christina C. Williams, Min Yun, Jorge A. Zavala, Milagros Zeballos

Astronomy: Faculty Publications

We directly detect dust emission in an optically detected, multiply imaged galaxy lensed by the Frontier Fields cluster MACSJ0717.5+3745. We detect two images of the same galaxy at 1.1 mm with the AzTEC camera on the Large Millimeter Telescope leaving no ambiguity in the counterpart identification. This galaxy, MACS0717_Az9, is at z > 4 and the strong lensing model (μ=7.5) allows us to calculate an intrinsic IR luminosity of 9.7 × 1010 Le and an obscured star formation rate of 14.6 ± 4.5 Me yr−1. The unobscured star formation rate from the UV is only 4.1 ± 0.3 Me yr−1, which …


The Extinction Properties Of And Distance To The Highly Reddened Type Ia Supernova Sn 2012cu, Xiaosheng Huang, Z. Raha, G. Aldering, P. Antilogus, S. Bailey, C. Baltay, K. Barbary, D. Baugh, K. Boone, S. Bongard, C. Buton, J. Chen, N. Chotard, Y. Copin, P. Fagrelius, H. K. Fakhouri, U. Feindt, D. Fouchez, E. Gangler, B. Hayden, W. Hillebrandt, A. G. Kim, M. Kowalski, P. F. Leget, S. Lombardo, J. Nordin, R. Pain, E. Pecontal, R. Pereira, S. Perlmutter, D. Rabinowitz, M. Rigault, D. Rubin, K. Runge, C. Saunders, G. Smadja, C. Sofiatti, A. Stocker, N. Suzuki, S. Taubenberger, C. Tao, R. C. Thomas Feb 2017

The Extinction Properties Of And Distance To The Highly Reddened Type Ia Supernova Sn 2012cu, Xiaosheng Huang, Z. Raha, G. Aldering, P. Antilogus, S. Bailey, C. Baltay, K. Barbary, D. Baugh, K. Boone, S. Bongard, C. Buton, J. Chen, N. Chotard, Y. Copin, P. Fagrelius, H. K. Fakhouri, U. Feindt, D. Fouchez, E. Gangler, B. Hayden, W. Hillebrandt, A. G. Kim, M. Kowalski, P. F. Leget, S. Lombardo, J. Nordin, R. Pain, E. Pecontal, R. Pereira, S. Perlmutter, D. Rabinowitz, M. Rigault, D. Rubin, K. Runge, C. Saunders, G. Smadja, C. Sofiatti, A. Stocker, N. Suzuki, S. Taubenberger, C. Tao, R. C. Thomas

Physics and Astronomy

Correcting Type Ia Supernova brightnesses for extinction by dust has proven to be a vexing problem. Here we study the dust foreground to the highly reddened SN 2012cu, which is projected onto a dust lane in the galaxy NGC 4772. The analysis is based on multi-epoch, spectrophotometric observations spanning from 3300–9200 Å, obtained by the Nearby Supernova Factory. Phase-matched comparison of the spectroscopically twinned SN 2012cu and SN 2011fe across 10 epochs results in the best-fit color excess of (, RMS) = (1.00, 0.03) and total-to-selective extinction ratio of (R V , RMS) = (2.95, 0.08) toward SN 2012cu …


Structure And Physical Conditions In The Huygens Region Of The Orion Nebula, C. R. O'Dell, Gary J. Ferland, M. Peimbert Oct 2016

Structure And Physical Conditions In The Huygens Region Of The Orion Nebula, C. R. O'Dell, Gary J. Ferland, M. Peimbert

Physics and Astronomy Faculty Publications

Hubble Space Telescope images, MUSE maps of emission lines, and an atlas of high velocity resolution emission-line spectra have been used to establish for the first time correlations of the electron temperature, electron density, radial velocity, turbulence, and orientation within the main ionization front of the nebula. From the study of the combined properties of multiple features, it is established that variations in the radial velocity are primarily caused by the photoevaporating ionization front being viewed at different angles. There is a progressive increase of the electron temperature and density with decreasing distance from the dominant ionizing star θ1 …


Peering Through The Dust: Nustar Observations Of Two First-2mass Red Quasars, Stephanie M. Lamassa, Angelo Ricarte, Eilat Glikman, C. Megan Urry, Daniel Stern, Tahir Yaqoob, George B. Lansbury, Francesca Civano Mar 2016

Peering Through The Dust: Nustar Observations Of Two First-2mass Red Quasars, Stephanie M. Lamassa, Angelo Ricarte, Eilat Glikman, C. Megan Urry, Daniel Stern, Tahir Yaqoob, George B. Lansbury, Francesca Civano

Dartmouth Scholarship

Some reddened quasars appear to be transitional objects in the merger-induced black hole growth/galaxy evolution paradigm, where a heavily obscured nucleus starts to be unveiled by powerful quasar winds evacuating the surrounding cocoon of dust and gas. Hard X-ray observations are able to peer through this gas and dust, revealing the properties of circumnuclear obscuration. Here, we present NuSTAR and XMM-Newton/Chandra observations of FIRST-2MASS selected red quasars F2M 0830+3759 and F2M 1227+3214. We find that though F2M 0830+3759 is moderately obscured (NH,Z=2.1±0.2×1022 cm−2) and F2M 1227+3214 is mildly absorbed (NH,Z=3.4+0.8−0.7×1021 cm−2 …


Herschel Dust Emission As A Probe Of Starless Cores Mass: Mcld 123.5+24.9 Of The Polaris Flare, Gururaj Anil Wagle, Thomas H. Troland, Gary J. Ferland, Nicholas P. Abel Aug 2015

Herschel Dust Emission As A Probe Of Starless Cores Mass: Mcld 123.5+24.9 Of The Polaris Flare, Gururaj Anil Wagle, Thomas H. Troland, Gary J. Ferland, Nicholas P. Abel

Physics and Astronomy Faculty Publications

We present newly processed archival Herschel images of molecular cloud MCLD 123.5+24.9 in the Polaris Flare. This cloud contains five starless cores. Using the spectral synthesis code Cloudy, we explore uncertainties in the derivation of column densities, and hence masses of molecular cores from Herschel data. We first consider several detailed grain models that predict far-infrared grain opacities. Opacities predicted by the models differ by more than a factor of two, leading to uncertainties in derived column densities by the same factor. Then we consider uncertainties associated with the modified blackbody fitting process used by observers to estimate column densities. …


The Dependence Of The Av Prior For Sn Ia On Host Mass And Disc Inclination., Benne W. Holwerda, W. C. Keel, M. A. Kenworthy, K. J. Mack Aug 2015

The Dependence Of The Av Prior For Sn Ia On Host Mass And Disc Inclination., Benne W. Holwerda, W. C. Keel, M. A. Kenworthy, K. J. Mack

Faculty Scholarship

Type Ia supernovae (SNe Ia) are used as ‘standard candles’ for cosmological distance scales. To fit their light-curve shape–absolute luminosity relation, one needs to assume an intrinsic colour and a likelihood of host galaxy extinction or a convolution of these, a colour distribution prior. The host galaxy extinction prior is typically assumed to be an exponential drop-off for the current supernova programmes ( P(AV)∝e−AV/τ0" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-variant: inherit; font-stretch: inherit; line-height: normal; font-family: inherit; vertical-align: baseline; display: inline-table; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: …


Observational Properties Of Simulated Galaxies In Overdense And Average Regions At Redshifts Z ≃ 6–12, Hidenobu Yajima, Isaac Shlosman, Emilio Romano-Díaz, Kentaro Nagamine Jul 2015

Observational Properties Of Simulated Galaxies In Overdense And Average Regions At Redshifts Z ≃ 6–12, Hidenobu Yajima, Isaac Shlosman, Emilio Romano-Díaz, Kentaro Nagamine

Physics and Astronomy Faculty Publications

We use high-resolution zoom-in cosmological simulations of galaxies of Romano-Díaz et al., post-processing them with a panchromatic three-dimensional radiation transfer code to obtain the galaxy UV luminosity function (LF) at z ≃ 6–12. The galaxies are followed in a rare, heavily overdense region within a ∼5σ density peak, which can host high-z quasars, and in an average density region, down to the stellar mass of Mstar ∼ 4 × 107 M. We find that the overdense regions evolve at a substantially accelerated pace – the most massive galaxy has grown to Mstar ∼ 8.4 …


Origin Of The Diffuse, Far Ultraviolet Emission In The Interarm Regions Of M101., Alison F. Crocker, Rupali Chandar, Daniela Calzetti, Benne W. Holwerda, Claus Leitherer, Cristina C. Popescu, R. J. Tuffs Jul 2015

Origin Of The Diffuse, Far Ultraviolet Emission In The Interarm Regions Of M101., Alison F. Crocker, Rupali Chandar, Daniela Calzetti, Benne W. Holwerda, Claus Leitherer, Cristina C. Popescu, R. J. Tuffs

Faculty Scholarship

We present images from the Solar Blind Channel on the Hubble Space Telescope that resolve hundreds of farultraviolet (FUV) emitting stars in two ∼1 kpc2 interarm regions of the grand-design spiral M101. The luminosity functions of these stars are compared with predicted distributions from simple star formation histories, and are best reproduced when the star formation rate has recently declined (past 10–50 Myr). This pattern is consistent with stars forming within spiral arms and then streaming into the interarm regions. We measure the diffuse FUV surface brightness after subtracting all of the detected stars, clusters, and background galaxies. A residual …


Galaxy And Mass Assembly (Gama) Blended Spectra Catalogue : Strong Galaxy–Galaxy Lens And Occulting Galaxy Pair Candidates., Benne W. Holwerda, I. K. Baldry, M. Alpaslan, A. E. Bauer, J. Bland-Hawthorn, S. Brough, M. J. I. Brown, M. E. Cluver, C. J. Conselice, S. P. Driver, A. M. Hopkins, D. H. Jones, Angel R. Lopez-Sanchez, J. Loveday, M. J. Meyer, A. Moffett Jun 2015

Galaxy And Mass Assembly (Gama) Blended Spectra Catalogue : Strong Galaxy–Galaxy Lens And Occulting Galaxy Pair Candidates., Benne W. Holwerda, I. K. Baldry, M. Alpaslan, A. E. Bauer, J. Bland-Hawthorn, S. Brough, M. J. I. Brown, M. E. Cluver, C. J. Conselice, S. P. Driver, A. M. Hopkins, D. H. Jones, Angel R. Lopez-Sanchez, J. Loveday, M. J. Meyer, A. Moffett

Faculty Scholarship

We present the catalogue of blended galaxy spectra from the Galaxy And Mass Assembly (GAMA) survey. These are cases where light from two galaxies are significantly detected in a single GAMA fibre. Galaxy pairs identified from their blended spectrum fall into two principal classes: they are either strong lenses, a passive galaxy lensing an emission-line galaxy; or occulting galaxies, serendipitous overlaps of two galaxies, of any type. Blended spectra can thus be used to reliably identify strong lenses for follow-up observations (high-resolution imaging) and occulting pairs, especially those that are a late-type partly obscuring an early-type galaxy which are of …


The Dust Geometric Distribution In Seyfert 1 And Seyfert 2 Galaxies, Isolated And In Interaction, S. Mendoza-Castrejón, D. Dultzin, Y. Krongold, J. J. González, Moshe Elitzur Mar 2015

The Dust Geometric Distribution In Seyfert 1 And Seyfert 2 Galaxies, Isolated And In Interaction, S. Mendoza-Castrejón, D. Dultzin, Y. Krongold, J. J. González, Moshe Elitzur

Physics and Astronomy Faculty Publications

We analyse the mid-infrared (MIR) spectra of 39 Seyfert galaxies observed with the Infrared Spectrograph (IRS) on board the Spitzer Space Telescope. Our sample consists of 19 Seyfert type 1 (Sy1) galaxies, three intermediate Seyfert galaxies and 17 type 2 Seyfert (Sy2) galaxies in the nearby Universe. This sample was extracted from a larger sample, the circumgalactic environment of which was studied in a previous work by Dultzin-Hacyan et al., who found that Sy2 objects are in interaction more frequently than normal galaxies, while Sy1s are not. In this article, we study the silicate dust distribution that dominates the …


Sn Ia Host Galaxy Properties And The Dust Extinction Distribution., Benne W. Holwerda, A. Reynolds, M. Smith, R. C. Kraan-Korteweg Feb 2015

Sn Ia Host Galaxy Properties And The Dust Extinction Distribution., Benne W. Holwerda, A. Reynolds, M. Smith, R. C. Kraan-Korteweg

Faculty Scholarship

Type Ia supernovae (SNeIa) display a complex relation with their host galaxies. An important prior to the fit of the supernovae's light curve is the distribution of host galaxy extinction values that can be encountered. The Sloan Digital Sky Survey SuperNova survey project has published light-curve fits using both mlcs2k2 and salt2. We use the former fits extinction parameter (AV) to map this distribution of extinction values. We explore the dependence of this distribution on four observables; the inclination of the host galaxy disc, radial position of the supernova, redshift of the supernova and host, and the level …


The Sdss–2mass–Wise 10 Dimensional Stellar Color Locus, James R. A. Davenport, Željko Ivezić, Andrew C. Becker, John J. Ruan, Nicholas M. Hunt-Walker, Kevin R. Covey, Alexia R. Lewis, Yusra Alsayyad, Lauren M. Anderson Jun 2014

The Sdss–2mass–Wise 10 Dimensional Stellar Color Locus, James R. A. Davenport, Željko Ivezić, Andrew C. Becker, John J. Ruan, Nicholas M. Hunt-Walker, Kevin R. Covey, Alexia R. Lewis, Yusra Alsayyad, Lauren M. Anderson

Physics & Astronomy

We present the fiducial main-sequence stellar locus traced by 10 photometric colours observed by Sloan Digital Sky Survey (SDSS), Two Micron All Sky Survey (2MASS), and Wide-field Infrared Survey Explorer(WISE). Median colours are determined using 1052 793 stars with r-band extinction less than 0.125. We use this locus to measure the dust extinction curve relative to the r band, which is consistent with previous measurements in the SDSS and 2MASS bands. The WISE band extinction coefficients are larger than predicted by standard extinction models. Using 13 lines of sight, we find variations in the extinction curve …


Illuminating The Darkest Gamma-Ray Bursts With Radio Observations, B.A. Zauderer, E. Berger, R. Margutti, A.J. Levan, F. Olivares E., D.A. Perley, W. Fong, A. Horesh, Adria Updike, J. Greiner, N.R. Tanvir, T. Laskar, R. Chornock, A.M. Soderberg, K.M. Menten, E. Nakar, J. Carpenter, P. Chandra, A.J. Castro-Tirado, M. Bremer, J. Gorosabel, S. Guziy, D. P´Erez-Ram´Irez, J.M. Winters Jan 2013

Illuminating The Darkest Gamma-Ray Bursts With Radio Observations, B.A. Zauderer, E. Berger, R. Margutti, A.J. Levan, F. Olivares E., D.A. Perley, W. Fong, A. Horesh, Adria Updike, J. Greiner, N.R. Tanvir, T. Laskar, R. Chornock, A.M. Soderberg, K.M. Menten, E. Nakar, J. Carpenter, P. Chandra, A.J. Castro-Tirado, M. Bremer, J. Gorosabel, S. Guziy, D. P´Erez-Ram´Irez, J.M. Winters

Arts & Sciences Faculty Publications

No abstract provided.


Galaxy Zoo : A Catalog Of Overlapping Galaxy Pairs For Dust Studies., William C. Keel, Anna M. Manning, Benne W. Holwerda, Massimo Mezzoprete, Chris J. Lintott, Kevin Schawinski, Pamela Gay, Karen L. Masters Jan 2013

Galaxy Zoo : A Catalog Of Overlapping Galaxy Pairs For Dust Studies., William C. Keel, Anna M. Manning, Benne W. Holwerda, Massimo Mezzoprete, Chris J. Lintott, Kevin Schawinski, Pamela Gay, Karen L. Masters

Faculty Scholarship

Analysis of galaxies with overlapping images offers a direct way to probe the distribution of dust extinction and its effects on the background light. We present a catalog of 1990 such galaxy pairs selected from the Sloan Digital Sky Survey (SDSS) by volunteers of the Galaxy Zoo project. We highlight subsamples which are particularly useful for retrieving such properties of the dust distribution as UV extinction, the extent perpendicular to the disk plane, and extinction in the inner parts of disks. The sample spans wide ranges of morphology and surface brightness, opening up the possibility of using this technique to …


Pumping Up The [N I] Nebular Lines, Gary J. Ferland, W. J. Henney, C. R. O'Dell, R. L. Porter, P. A. M. Vanhoof, R. J. R. Williams Sep 2012

Pumping Up The [N I] Nebular Lines, Gary J. Ferland, W. J. Henney, C. R. O'Dell, R. L. Porter, P. A. M. Vanhoof, R. J. R. Williams

Physics and Astronomy Faculty Publications

The optical [N I] doublet near 5200 Å is anomalously strong in a variety of emission-line objects. We compute a detailed photoionization model and use it to show that pumping by far-ultraviolet (FUV) stellar radiation previously posited as a general explanation applies to the Orion Nebula (M42) and its companion M43; but, it is unlikely to explain planetary nebulae and supernova remnants. Our models establish that the observed nearly constant equivalent width of [N I] with respect to the dust-scattered stellar continuum depends primarily on three factors: the FUV to visual-band flux ratio of the stellar population, the optical properties …


Herschel Observations Of Extended Atomic Gas In The Core Of The Perseus Cluster, R. Mittal, J. B. R. Oonk, Gary J. Ferland, A. C. Edge, C. P. O'Dea, S. A. Baum, J. T. Whelan, R. M. Johnstone, F. Combes, P. Salomé, A. C. Fabian, G. R. Tremblay, M. Donahue, Russell H. H. Jan 2012

Herschel Observations Of Extended Atomic Gas In The Core Of The Perseus Cluster, R. Mittal, J. B. R. Oonk, Gary J. Ferland, A. C. Edge, C. P. O'Dea, S. A. Baum, J. T. Whelan, R. M. Johnstone, F. Combes, P. Salomé, A. C. Fabian, G. R. Tremblay, M. Donahue, Russell H. H.

Physics and Astronomy Faculty Publications

We present Herschel observations of the core of the Perseus cluster of galaxies. Especially intriguing is the network of filaments that surround the brightest cluster galaxy, NGC 1275, previously imaged extensively in Hα and CO. In this work, we report detections of far-infrared (FIR) lines, in particular, [C II] 158, [O I] 63, [N II] 122, [O IB] 145 and [O III] 88  μm, withHerschel. All lines are spatially extended, except [O III], with the [C II] line emission extending up to 25 kpc from the core. [C II] emission is found to be co-spatial with Hα and …


Dust And The Type Ii-Plateau Supernova 2004dj, W. P. S. Meikle, R. Kotak, D. Farrah, S. Mattila, S. D. Van Dyk, A. C. Andersen, R. Fesen Apr 2011

Dust And The Type Ii-Plateau Supernova 2004dj, W. P. S. Meikle, R. Kotak, D. Farrah, S. Mattila, S. D. Van Dyk, A. C. Andersen, R. Fesen

Dartmouth Scholarship

We present mid-infrared (MIR) spectroscopy of a Type II-plateau supernova, SN 2004dj, obtained with the Spitzer Space Telescope, spanning 106-1393 days after explosion. MIR photometry plus optical/near-IR observations are also reported. An early-time MIR excess is attributed to emission from non-silicate dust formed within a cool dense shell (CDS). Most of the CDS dust condensed between 50 days and 165 days, reaching a mass of 0.3 × 10–5 M . Throughout the observations, much of the longer wavelength (>10 μm) part of the continuum is explained as an IR echo from interstellar dust. The MIR excess …


Monster In The Dark: The Ultraluminous Grb 080607 And Its Dusty Environment, D.A. Perley, A.N. Morgan, Adria Updike, F. Yuan, C.W. Akerlof, A.A. Miller, J.S. Bloom, S.B. Cenko, W. Li, A.V. Filippenko, J.X. Prochaska, D.A. Kann, N.R. Tanvir, A.J. Levan, N.R. Butler, P. Christian, D.H. Hartmann, P. Milne, E.S. Rykoff, W. Rujopakarn, J.C. Wheeler, G.G. Williams Jan 2011

Monster In The Dark: The Ultraluminous Grb 080607 And Its Dusty Environment, D.A. Perley, A.N. Morgan, Adria Updike, F. Yuan, C.W. Akerlof, A.A. Miller, J.S. Bloom, S.B. Cenko, W. Li, A.V. Filippenko, J.X. Prochaska, D.A. Kann, N.R. Tanvir, A.J. Levan, N.R. Butler, P. Christian, D.H. Hartmann, P. Milne, E.S. Rykoff, W. Rujopakarn, J.C. Wheeler, G.G. Williams

Arts & Sciences Faculty Publications

We present early-time optical through infrared photometry of the bright Swift gamma-ray burst (GRB) 080607, starting only 6 s following the initial trigger in the rest frame. Complemented by our previously published spectroscopy, this high-quality photometric data set allows us to solve for the extinction properties of the redshift 3.036 sightline, giving perhaps the most detailed information to date on the ultraviolet continuum absorption properties of any sightline outside our Local Group. The extinction properties are not adequately modeled by any ordinary extinction template (including the average Milky Way, Large Magellanic Cloud, and Small Magellanic Cloud curves), partially because the …


The Seds And Host Galaxies Of The Dustiest Grb Afterglows, T. Krühler, J. Greiner, P. Schady, S. Savaglio, P. M.J. Afonso, C. Clemens, J. Elliott, R. Filgas, D. Gruber, D. A. Kann, S. Klose, A. Küpcü-Yoldas, S. Mcbreen, F. Olivares, D. Pierini, A. Rau, A. Rossi, M. Nardini, A. Nicuesa Guelbenzu, V. Sudilovsky, Adria Updike Jan 2011

The Seds And Host Galaxies Of The Dustiest Grb Afterglows, T. Krühler, J. Greiner, P. Schady, S. Savaglio, P. M.J. Afonso, C. Clemens, J. Elliott, R. Filgas, D. Gruber, D. A. Kann, S. Klose, A. Küpcü-Yoldas, S. Mcbreen, F. Olivares, D. Pierini, A. Rau, A. Rossi, M. Nardini, A. Nicuesa Guelbenzu, V. Sudilovsky, Adria Updike

Arts & Sciences Faculty Publications

No abstract provided.


Evidence For The Supernova-Synthesized Dust From The Rising Afterglow Of Grb071025 At Z ∼ 5, Daniel A. Perley, J. S. Bloom, C. R. Klein, S. Covino, T. Minezaki, P. Wozniak, W. T. Vestrand, G. G. Williams, P. Milne, N R. Butler, A C. Updike, T Kruhler, P Afonso, A Antonelli, L Cowie, P Ferrero, J Greiner, Dieter H. Hartmann, Y Kakazu, A Küpcü Yoldaş, A N. Morgan, P A. Price, J X. Prochaska, Y Yoshii Jul 2010

Evidence For The Supernova-Synthesized Dust From The Rising Afterglow Of Grb071025 At Z ∼ 5, Daniel A. Perley, J. S. Bloom, C. R. Klein, S. Covino, T. Minezaki, P. Wozniak, W. T. Vestrand, G. G. Williams, P. Milne, N R. Butler, A C. Updike, T Kruhler, P Afonso, A Antonelli, L Cowie, P Ferrero, J Greiner, Dieter H. Hartmann, Y Kakazu, A Küpcü Yoldaş, A N. Morgan, P A. Price, J X. Prochaska, Y Yoshii

Publications

We present observations and analysis of the broad-band afterglow of Swift GRB 071025. Using optical and infrared (RIYJHK) photometry, we derive a photometric redshift of 4.4 < 5.2; at this redshift our simultaneous multicolour observations begin at ∼30 s after the gamma-ray burst trigger in the host frame, during the initial rising phase of the afterglow. We associate the light-curve peak at ∼580 s in the observer frame with the formation of the forward shock, giving an estimate of the initial Lorentz factor 0 ∼ 200. The red spectral energy distribution (even in regions not affected by the Lyman α break) provides secure evidence of a large dust column. However, the inferred extinction curve shows a prominent flat component between 2000 and 3000 Å in the rest frame, inconsistent with any locally observed template but well fitted by models of dust formed by supernovae. Time-dependent fits to the extinction profile reveal no evidence of dust destruction and limit the decrease in the extinction column to A3000 < 0.54 mag after t = 50 s in the rest frame. Together with studies of high-z quasars, our observations suggest a transition in dust properties in the early Universe, possibly associated with a transition between supernova-dominated and asymptotic giant branch-dominated modes of dust production.


Herschel Images Of Ngc 6720: H2 Formation On Dust Grain, P. A. M. Van Hoof, G. C. Van De Steene, M. J. Barlow, K. M. Exter, B. Sibthorpe, T. Ueta, V. Peris, M. A. T. Groenewegen, J. A. D. L. Blommaert, M. Cohen, W. De Meester, Gary J. Ferland, W. K. Gear, H. L. Gomez, P. C. Hargrave, E. Huygen, R. J. Ivison, C. Jean, S. J. Leeks, T. L. Lim, G. Olofsson, E. T. Polehampton, S. Regibo, P. Royer, B. M. Swinyard, B. Vandenbussche, H. Van Winckel, C. Waelkens, H. J. Walker, R. Wesson Jul 2010

Herschel Images Of Ngc 6720: H2 Formation On Dust Grain, P. A. M. Van Hoof, G. C. Van De Steene, M. J. Barlow, K. M. Exter, B. Sibthorpe, T. Ueta, V. Peris, M. A. T. Groenewegen, J. A. D. L. Blommaert, M. Cohen, W. De Meester, Gary J. Ferland, W. K. Gear, H. L. Gomez, P. C. Hargrave, E. Huygen, R. J. Ivison, C. Jean, S. J. Leeks, T. L. Lim, G. Olofsson, E. T. Polehampton, S. Regibo, P. Royer, B. M. Swinyard, B. Vandenbussche, H. Van Winckel, C. Waelkens, H. J. Walker, R. Wesson

Physics and Astronomy Faculty Publications

Herschel PACS and SPIRE images have been obtained of NGC 6720 (the Ring nebula). This is an evolved planetary nebula with a central star that is currently on the cooling track, due to which the outer parts of the nebula are recombining. From the PACS and SPIRE images we conclude that there is a striking resemblance between the dust distribution and the H2 emission, which appears to be observational evidence that H2 forms on grain surfaces. We have developed a photoionization model of the nebula with the Cloudy code which we used to determine the physical conditions of …


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 …


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 Jan 2010

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 …


The Relation Between Gas And Dust In The Taurus Molecular Cloud, G Pineda, P Goldsmith, N Chapman, Ronald L. Snell, D Li, L Cambresy, C Brunt Jan 2010

The Relation Between Gas And Dust In The Taurus Molecular Cloud, G Pineda, P Goldsmith, N Chapman, Ronald L. Snell, D Li, L Cambresy, C Brunt

Astronomy Department Faculty Publication Series

We report a study of the relation between dust and gas over a 100 deg2 area in the Taurus molecular cloud. We compare the H2 column density derived from dust extinction with the CO column density derived from the 12CO and 13CO J = 1 → 0 lines. We derive the visual extinction from reddening determined from 2MASS data. The comparison is done at an angular size of 200'' corresponding to 0.14 pc at a distance of 140 pc. We find that the relation between visual extinction A V and N(CO) is linear between A …


The Afterglows Of Swift-Era Gamma-Ray Bursts. I. Comparing Pre-Swift And Swift-Era Long/Soft (Type Ii) Grb Optical Afterglows, D. A. Kann, S. Klose, B. Zhang, D. Malesani, E. Nakar, A. Pozanenko, A. C. Wilson, N. R. Butler, P. Jakobsson, S. Schulze, M. Andreev, L. A. Antonelli, I. F. Bikmaev, V. Biryukov, M. B¨Ottcher, R. A. Burenin, J. M. Castro Cer´On, A. J. Castro-Tirado, G. Chincarini, B. E. Cobb, S. Covino, P. D’Avanzo, V. D’Elia, M. Della Valle, A. De Ugarte Postigo, Yu Efimov, P. Ferrero, D. Fugazza, D. Fugazza, J. P.U. Fynbo, M. Gålfalk, F. Grundahl, J. Gorosabel, S. Gupta, S. Guziy, B. Hafizov, J. Hjorth, K. Holhjem, M. Ibrahimov, M. Im, G. L. Israel, M. Je´Linek, B. L. Jensen, R. Karimov, I. M. Khamitov, U. KizilogˇLu, E. Klunko, P. Kuba´Nek, A. S. Kutyrev, P. Laursen, A. J. Levan, F. Mannucci, C. M. Martin, A. Mescheryakov, N. Mirabal, J. P. Norris, J. -E. Ovaldsen, D. Paraficz, E. Pavlenko, S. Piranomonte, A. Rossi, V. Rumyantsev, R. Salinas, A. Sergeev, D. Sharapov, J. Sollerman, B. Stecklum, L. Stella, G. Tagliaferri, N. R. Tanvir, J. Telting, V. Testa, Adria Updike, A. Volnova, D. Watson, K. Wiersema, D. Xu Jan 2010

The Afterglows Of Swift-Era Gamma-Ray Bursts. I. Comparing Pre-Swift And Swift-Era Long/Soft (Type Ii) Grb Optical Afterglows, D. A. Kann, S. Klose, B. Zhang, D. Malesani, E. Nakar, A. Pozanenko, A. C. Wilson, N. R. Butler, P. Jakobsson, S. Schulze, M. Andreev, L. A. Antonelli, I. F. Bikmaev, V. Biryukov, M. B¨Ottcher, R. A. Burenin, J. M. Castro Cer´On, A. J. Castro-Tirado, G. Chincarini, B. E. Cobb, S. Covino, P. D’Avanzo, V. D’Elia, M. Della Valle, A. De Ugarte Postigo, Yu Efimov, P. Ferrero, D. Fugazza, D. Fugazza, J. P.U. Fynbo, M. Gålfalk, F. Grundahl, J. Gorosabel, S. Gupta, S. Guziy, B. Hafizov, J. Hjorth, K. Holhjem, M. Ibrahimov, M. Im, G. L. Israel, M. Je´Linek, B. L. Jensen, R. Karimov, I. M. Khamitov, U. KizilogˇLu, E. Klunko, P. Kuba´Nek, A. S. Kutyrev, P. Laursen, A. J. Levan, F. Mannucci, C. M. Martin, A. Mescheryakov, N. Mirabal, J. P. Norris, J. -E. Ovaldsen, D. Paraficz, E. Pavlenko, S. Piranomonte, A. Rossi, V. Rumyantsev, R. Salinas, A. Sergeev, D. Sharapov, J. Sollerman, B. Stecklum, L. Stella, G. Tagliaferri, N. R. Tanvir, J. Telting, V. Testa, Adria Updike, A. Volnova, D. Watson, K. Wiersema, D. Xu

Arts & Sciences Faculty Publications

We have gathered optical photometry data from the literature on a large sample of Swift-era gamma-ray burst (GRB) afterglows including GRBs up to 2009 September, for a total of 76 GRBs, and present an additional three pre-Swift GRBs not included in an earlier sample. Furthermore, we publish 840 additional new photometry data points on a total of 42 GRB afterglows, including large data sets for GRBs 050319, 050408, 050802, 050820A, 050922C, 060418, 080413A, and 080810. We analyzed the light curves of all GRBs in the sample and derived spectral energy distributions for the sample with the best data quality, allowing …


Evidence For Supernova-Synthesized Dust From The Rising Afterglow Of Grb071025 At Z ∼ 5, Daniel A. Perley, J. S. Bloom, C. R. Klein, S. Covino, T. Minezaki, P. Wo´Zniak, W. T. Vestrand, G. G. Williams, P. Milne, N. R. Butler, Adria Updike, T. Kr¨Uhler, P. Afonso, A. Antonelli, L. Cowie, P. Ferrero, J. Greiner, D. H. Hartmann, Y. Kakazu, A. K¨Upc¨U Yoldas¸, A. N. Morgan, P. A. Price, J. X. Prochaska, Y. Yoshii Jan 2010

Evidence For Supernova-Synthesized Dust From The Rising Afterglow Of Grb071025 At Z ∼ 5, Daniel A. Perley, J. S. Bloom, C. R. Klein, S. Covino, T. Minezaki, P. Wo´Zniak, W. T. Vestrand, G. G. Williams, P. Milne, N. R. Butler, Adria Updike, T. Kr¨Uhler, P. Afonso, A. Antonelli, L. Cowie, P. Ferrero, J. Greiner, D. H. Hartmann, Y. Kakazu, A. K¨Upc¨U Yoldas¸, A. N. Morgan, P. A. Price, J. X. Prochaska, Y. Yoshii

Arts & Sciences Faculty Publications

No abstract provided.