Branch, David, Dang, Leeann Chau, Baron, E.
A comparative study of optical spectra of Type Ia supernovae (SNe Ia) is extended, in the light of new data. The discussion is framed in terms of the four groups defined in previous papers of this...
Late-Time HST Photometry of SN 1994I: Hints of Positron Annihilation Energy Deposition (2008)
Clocchiatti, Alejandro, Wheeler, J. Craig, Kirshner, Robert P., Branch, David, Challis, Peter, Chevalier, Roger A., ...
We present multicolor Hubble Space Telescope (HST) WFPC2 broadband observations of the Type Ic SN 1994I obtained approximately 280 days after maximum light. We measure the brightness of the SN and,...
Evidence for a Spectroscopic Sequence Among SNe Ia (2008)
Peter Nugent, Mark Phillips, E. Baron, David Branch, Peter Hauschildt
In this Letter we present evidence for a spectral sequence among Type Ia supernovae (SNe Ia). The sequence is based on the systematic variation of several features seen in the near-maximum light...
A Self-Consistent NLTE-Spectra Synthesis Model of FeLoBAL QSOs (2008)
Casebeer, Darrin, Baron, E., Leighly, Karen, Jevremovic, Darko, Branch, David
We present detailed radiative transfer spectral synthesis models for the Iron Low Ionization Broad Absorption Line (FeLoBAL) active galactic nuclei (AGN) FIRST J121442.3+280329 and ISO...
Comparative Direct Analysis of Type Ia Supernova Spectra. IV. Postmaximum (2007)
Branch, David, Jeffery, David J., Parrent, Jerod, Baron, E., Troxel, M. A., Stanishev, V., ...
A comparative study of optical spectra of Type Ia supernovae (SNe Ia) obtained near 1 week, 3 weeks, and 3 months after maximum light is presented. Most members of the four groups that were defined...
Peter Nugent, E. Baron, David Branch, Adam Fisher, Peter H. Hauschildt
We present detailed NLTE synthetic spectra of hydrodynamic SNe Ia models. We make no assumptions about the form of the spectrum at the inner boundary. We calculate both Chandrasekhar-mass...
Metallicity Effects in NLTE Model Atmospheres of Type Ia Supernovae (2007)
Eric Lentz Baron, Eric J. Lentz, E. Baron, David Branch, Peter H. Hauschildt, Peter E. Nugent
We have calculated a grid of photospheric phase atmospheres of Type Ia supernovae (SNe Ia) with metallicities from ten times to one thirtieth the solar metallicity in the C+O layer of the...
Direct Analysis of Spectra of the Type Ic Supernova 1994I (2007)
Jennifer Millard, David Branch, E. Baron, Adam Fisher, A. V. Filippenko, R. P. Kirshner, ...
Synthetic spectra generated by the parameterized supernova synthetic-- spectrum code SYNOW are compared to observed photospheric--phase spectra of the Type Ic supernova 1994I. The observed optical...
David Branch, W. Romanishin, E. Baron
Statistical connections between the properties of Type Ia supernovae (SNe Ia) and the B--V colors of their parent galaxies are established. Compared to SNe Ia in blue galaxies [(B \Gamma V ) o T ¸...
Peter Nugent, Mark Phillips, E. Baron, David Branch, Peter Hauschildt, Ni Produced
In this Letter we present evidence for a spectral sequence among Type Ia supernovae (SNe Ia). The sequence is based on the systematic variation of several features seen in the near-maximum light...
Peter Nugent, E. Baron, Peter H. Hauschildt, David Branch
We present NLTE synthetic spectra for the Type Ia supernovae SN 1992A and SN 1981B, near maximum light. At this epoch both supernovae were observed from the UV through the optical. This wide spectral...
ON VAN DEN BERGH'S METHOD FOR MEASURING THE HUBBLE CONSTANT FROM TYPE IA SUPERNOVAE (2007)
David Branch, Adam Fisher, E. Baron, Peter Nugent
In a recent Letter, van den Bergh used explosion--model light--curve calculations of Hoflich & Khokhlov to calibrate the Hamuy et al. sample of remote Type Ia supernovae (SNe Ia), and obtained...
Peter Nugent, E. Baron, David Branch, Adam Fisher, Peter H. Hauschildt
We present detailed NLTE synthetic spectra of hydrodynamic SNe Ia models. We make no assumptions about the form of the spectrum at the inner boundary. We calculate both Chandrasekhar-mass...
Spectral Models of the Type Ic SN 1994I in M51 (2007)
E. Baron, David Branch, Peter H. Hauschildt, R. P. Kirshner
We present detailed non-local thermodynamic equilibrium (NLTE) synthetic spectra for comparison with a time series of observed optical spectra of the Type Ic supernova 1994I which occurred in M51....
P. H. Hauschildt, E. Baron, Peter Nugent, David Branch, Cepheid Variable Stars
Abstract. We present NLTE synthetic spectra for the Type Ia supernovae SN 1992A SN 1981B, and SN 1991bg near maximum light. At this epoch both of the normal SNe Ia (SNe 1981b and 1992A) were observed...
Detailed Spectral Modeling of a 3-D Pulsating Reverse Detonation Model: Too Much Nickel (2007)
Baron, E., Jeffery, David J., Branch, David, Bravo, Eduardo, Garcia-Senz, Domingo, Hauschildt, Peter H.
We calculate detailed NLTE synthetic spectra of a Pulsating Reverse Detonation (PRD) model, a novel explosion mechanism for Type Ia supernovae. While the hydro models are calculated in 3-D, the...
Comparative Direct Analysis of Type Ia Supernova Spectra. III. Premaximum (2007)
Branch, David, Troxel, M. A., Jeffery, David J., Hatano, Kazuhito, Musco, Miriam, Parrent, Jerod, ...
A comparative study of spectra of 21 Type Ia supernovae (SNe Ia) obtained about one week before maximum light, and 8 spectra obtained 11 or more days before maximum, is presented. To a large extent...
Detailed Spectral Analysis of the Type Ib Supernova 1999dn. Paper I: Hydrogen-free Models (2007)
Ketchum, Wesley, Baron, E., Branch, David
We present spectral fits to five epochs of the typical Type Ib supernova 1999dn using the generalized, non-LTE, stellar atmospheres code PHOENIX. Our goal is threefold: to determine basic physical...
Progenitors of Type Ia Supernovae: Binary Stars with White Dwarf Companions (2007)
Parthasarathy, M., Branch, David, Jeffery, David J., Baron, E.
Type Ia SNe (SNe Ia) are thought to come from carbon-oxygen white dwarfs that accrete mass from binary companions until they approach the Chandrasekhar limit, ignite carbon, and undergo complete...
Reddening, Abundances, and Line Formation in SNe II (2007)
Baron, E., Branch, David, Hauschildt, Peter H.
We present detailed NLTE spectral synthesis models of the Type II supernova 2005cs, which occurred in M51 and for which the explosion time is well determined. We show that previous estimates for the...
Direct Analysis of Spectra of the Unusual Type Ib Supernova 2005bf (2007)
Parrent, Jerod, Branch, David, Troxel, M. A., Casebeer, D., Jeffery, David J., Ketchum, W., ...
Synthetic spectra generated with the parameterized supernova synthetic-spectrum code SYNOW are compared to spectra of the unusual Type Ib supernova 2005bf. We confirm the discovery by Folatelli et...
On the Progenitor of Supernova 1987A (2006)
Parthasarathy, M., Branch, David, Baron, E., Jeffery, David J.
A previously unpublished ultralow-dispersion spectrum of Sanduleak -69 202, the stellar progenitor of SN 1987A, is presented and the uncertain presupernova evolution of Sanduleak -69 202 is discussed.
On SN 2003fg: The Probable Super-Chandrasekhar-Mass SN Ia (2006)
Jeffery, David J., Branch, David, Baron, E.
Howell et al. have reported the discovery of SN Ia SN 2003fg (SNLS-03D3bb) and conclude that SN 2003fg is very likely a super-Chandrasekhar-mass SN Ia perhaps with a mass of order 2 solar masses....
Goodness-of-Fit Tests DIFF1 and DIFF2 for Locally-Normalized Supernova Spectra (2006)
Jeffery, David J., Ketchum, Wesley, Branch, David, Baron, E., Elmhamdi, Abouazza, Danziger, I. J.
Two quantitative tests DIFF1 and DIFF2 for measuring goodness-of-fit between two locally-normalized supernova spectra are presented. Locally-normalized spectra are obtained by dividing a spectrum by...
Phillips, M. M., Garnavich, Peter, Wang, Yun, Branch, David, Baron, Edward, Crotts, Arlin, ...
JEDI (Joint Efficient Dark-energy Investigation) is a candidate implementation of the NASA-DOE Joint Dark Energy Mission (JDEM). JEDI will probe dark energy in three independent methods: (1) type Ia...
Hydrogen in Type Ic Supernovae? (2006)
Branch, David, Jeffery, David J., Young, Timothy R., Baron, E.
By definition, a Type Ic supernova (SN Ic) does not have conspicuous lines of hydrogen or helium in its optical spectrum. SNe Ic usually are modelled in terms of the gravitational collapse of bare...
Spectropolarimetry of the Peculiar Type Ia SN 2005hk (2006)
Chornock, Ryan, Filippenko, Alexei V., Branch, David, Foley, Ryan J., Jha, Saurabh, Li, Weidong
We present Keck spectropolarimetry of the unusual type Ia supernova (SN Ia) 2005hk several days before maximum light. An analysis of the high signal-to-noise-ratio total-flux spectrum shows the...
Spectral Modeling of SNe Ia Near Maximum Light: Probing the Characteristics of Hydro Models (2006)
Baron, E., Bongard, S., Branch, David, Hauschildt, Peter H.
We have performed detailed NLTE spectral synthesis modeling of 2 types of 1-D hydro models: the very highly parameterized deflagration model W7, and two delayed detonation models. We find that...
Late-Time Spectroscopy of SN 2002cx: The Prototype of a New Subclass of Type Ia Supernovae (2006)
Jha, Saurabh, Branch, David, Chornock, Ryan, Foley, Ryan J., Li, Weidong, Swift, Brandon J., ...
We present Keck optical spectra of SN 2002cx, the most peculiar known Type Ia supernova (SN Ia), taken 227 and 277 days past maximum light. Astonishingly, the spectra are not dominated by the...
Absolute-Magnitude Distributions and Light Curves of Stripped-Envelope Supernovae (2006)
Richardson, Dean, Branch, David, Baron, E.
The absolute visual magnitudes of three Type IIb, 11 Type Ib and 13 Type Ic supernovae (collectively known as stripped-envelope supernovae) are studied by collecting data on the apparent magnitude,...
Comparative Direct Analysis of Type Ia Supernova Spectra. II. Maximum Light (2006)
Branch, David, Dang, Leeann Chau, Hall, Nicholas, Ketchum, Wesley, Melakayil, Mercy, Parrent, Jerod, ...
A comparative study of near-maximum-light optical spectra of 24 Type Ia supernovae (SNe Ia) is presented. The spectra are quantified in two ways, and assigned to four groups. Seven "core-normal" SNe...
Using Line Profiles to Test the Fraternity of Type Ia Supernovae at High and Low Redshifts (2006)
Blondin, Stéphane, Dessart, Luc, Leibundgut, Bruno, Branch, David, Höflich, Peter, Tonry, John L., ...
Using archival data of low-redshift (z < 0.01; Center for Astrophysics and SUSPECT databases) Type Ia supernovae (SNe Ia) and recent observations of high-redshift (0.16 < z < 0.64) SNe Ia, we study...
Using Line Profiles to Test the Fraternity of Type Ia Supernovae at High and Low Redshifts (2006)
Blondin, Stéphane, Dessart, Luc, Leibundgut, Bruno, Branch, David, Höflich, Peter, Tonry, John L., ...
Using archival data of low-redshift (z < 0.01; Center for Astrophysics and SUSPECT databases) Type Ia supernovae (SNe Ia) and recent observations of high-redshift (0.16 < z < 0.64) SNe Ia, we study...
Type Ia Supernova Spectral Line Ratios as Luminosity Indicators (2005)
Bongard, Sebastien, Baron, E., Smadja, G., Branch, David, Hauschildt, Peter H.
Type Ia supernovae have played a crucial role in the discovery of the dark energy, via the measurement of their light curves and the determination of the peak brightness via fitting templates to the...
Type Ia Supernova Spectral Line Ratios as Luminosity Indicators (2005)
Bongard, Sebastien, Baron, E., Smadja, G., Branch, David, Hauschildt, Peter H.
Type Ia supernovae have played a crucial role in the discovery of the dark energy, via the measurement of their light curves and the determination of the peak brightness via fitting templates to the...
Quantitative Spectroscopy of Supernovae for Dark Energy Studies (2005)
Baron, E., Branch, David, Jeffery, David, Nugent, Peter, Thomas, Rollin, Bongard, Sebastien, ...
Detailed quantitative spectroscopy of Type Ia supernovae (SNe~Ia) provides crucial information needed to minimize systematic effects in both ongoing SNe Ia observational programs such as the Nearby...
Crotts, Arlin, Garnavich, Peter, Priedhorsky, William, Habib, Salman, Heitmann, Katrin, Wang, Yun, ...
JEDI will probe dark energy in three independent ways by measuring the expansion history of the universe: (1) using type Ia supernovae as cosmological standard candles over a range of distances, (2)...
Effects of Gravitational Microlensing on P-Cygni Profiles of Type Ia Supernovae (2005)
Bagherpour, Hamed, Branch, David, Kantowski, R.
A brief description of the deformed spectra of microlensed SNe Ia is presented. We show that microlensing amplification can have significant effects on line profiles. The resonance-scattering code...
Comparative Direct Analysis of Spectra of Type Ia Supernovae. I. SN 1994D (2005)
Branch, David, Baron, E., Hall, Nicholas, Melakayil, Mercy, Parrent, Jerod
As the first step in a comprehensive, comparative, direct analysis of the spectra of Type Ia supernovae (SNe Ia), we use the parameterized supernova synthetic-spectrum code, SYNOW, to interpret 26...
Light Curves of Microlensed Type Ia Supernovae (2004)
Bagherpour, Hamed, Kantowski, R., Branch, David, Richardson, Dean
A detailed description of the apparent light curves of microlensed SNe Ia as extended and expanding sources is presented. We show that microlensing amplification can have significant effects on...
Type IIP Supernovae as Cosmological Probes: A SEAM Distance to SN 1999em (2004)
Baron, E., Nugent, Peter, Branch, David, Hauschildt, Peter H.
Due to their intrinsic brightness, supernovae make excellent cosmological probes. We describe the SEAM method for obtaining distances to Type IIP supernovae (SNe IIP) and present a distance to SN...
Early Spectra of Supernovae (2004)
Baron, E., Nugent, Peter, Branch, David, Hauschildt, Peter H.
We briefly describe the current version of the PHOENIX code. We then present some results on the modeling of Type II supernovae and show that fits to observations can be obtained, when account is...
Reading the Spectra of the Most Peculiar Type Ia Supernova 2002cx (2004)
Branch, David, Baron, E., Thomas, R. C., Kasen, D., Li, Weidong, Filippenko, Alexei V.
In spite of the apparent lack of Si II and S II features in its spectra, SN 2002cx was classified as a peculiar Type Ia supernova (SN Ia) on the basis of its overall photometric and spectroscopic...
Type IIP supernovae as cosmological probes: A SEAM distance to SN 1999em (2004)
Baron, E., Nugent, Peter E., Branch, David, Hauschildt, Peter H.
Because of their intrinsic brightness, supernovae make excellent cosmological probes. We describe the spectral-fitting expanding atmosphere method (SEAM) for obtaining distances to Type IIP...
GRB 020410: A Gamma-ray burst afterglow discovered by its supernova light (2004)
Levan, Andrew, Nugent, Peter, Fruchter, Andrew, Burud, Ingunn, Branch, David, Rhoads, James, ...
We present the discovery and monitoring of the optical transient (OT) associated with GRB 020410. The fading OT was found by Hubble Space Telescope (HST) observations taken 28 and 65 days after burst...
Modeling AGN spectra with PHOENIX: a self-consistent approach (2004)
Casebeer, Darrin, Baron, Edward A., Branch, David, Leighly, Karen
We find that spectra of certain Iron Low Ionization Broad Absorption Line (FeLOBAL) QSOs, which are characterized by low--ionization emission and blue shifted absorption lines, can be well matched...
Type Ia Supernovae: Spectroscopic Surprises (2003)
Recent observations have extended the range of diversity among spectra of Type Ia supernovae. I briefly discuss SN Ia explosion models in the spectroscopic context, the observed diversity, and some...
On the Geometry of the High-Velocity Ejecta of the Peculiar Type Ia Supernova 2000cx (2003)
Thomas, R. C., Branch, David, Baron, E., Nomoto, Ken'ichi, Li, Weidong, Filippenko, Alexei V.
High-velocity features in Type Ia supernova spectra provide a way to probe the outer layers of these explosions. The maximum-light spectra of the unique Type Ia supernova 2000cx exhibit interesting...
Determination of Primordial Metallicity and Mixing in the Type IIP Supernova 1993W (2002)
Baron, E., Nugent, Peter E., Branch, David, Hauschildt, Peter H., Turatto, M., Cappellaro, E.
We present the results of a large grid of synthetic spectra and compare them to early spectroscopic observations of SN 1993W. This supernova was discovered close to its explosion date and at a...
Detectibility of Hydrogen Mixing in Type Ia Supernova pre-Maximum Spectra (2002)
Lentz, Eric J., Baron, E., Hauschildt, Peter H., Branch, David
The presence of a small amount of hydrogen is expected in most single degenerate scenarios for producing a Type Ia supernova (SN Ia). While hydrogen may be detected in very early high resolution...
Searching for Hydrogen in Type Ib Supernovae, and for Helium and Hydrogen in Type Ic (2002)
Identifying the progenitors of Type Ib and Type Ic supernovae requires knowing, among other things, whether SNe Ib eject hydrogen, and whether SNe Ic eject helium, and perhaps even hydrogen. Recently...
Synthetic Spectra from 3D Models of Supernovae (2002)
Thomas, R. C., Baron, E., Branch, David
We describe Brute, a code for generating synthetic spectra from 3D supernova models. It is based on a Monte Carlo implementation of the Sobolev approximation. The current version is highly...
Detailed spectroscopic analysis of SN 1987A: The distance to the LMC using the SEAM method (2002)
Mitchell, Robert C., Baron, E., Branch, David, Hauschildt, Peter H., Nugent, Peter E., Lundqvist, Peter, ...
Supernova 1987A remains the most well-studied supernova to date. Observations produced excellent broad-band photometric and spectroscopic coverage over a wide wavelength range at all epochs. We model...
Eck, Christopher R., Cowan, John J., Branch, David
We report VLA radio observations of 29 SNe with ages ranging from 10 days to about 90 years past explosion. These observations significantly contribute to the existing data pool on such objects....
Detailed Spectroscopic Analysis of SN 1987A: The Distance to the LMC using the SEAM method (2002)
Mitchell, Robert C., Baron, E., Branch, David, Hauschildt, Peter H., Nugent, Peter E., Lundqvist, Peter, ...
Supernova 1987A remains the most well-studied supernova to date. Observations produced excellent broad-band photometric and spectroscopic coverage over a wide wavelength range at all epochs. We model...
Pun, Chun S. J., Michael, Eli, Zhekov, Svetozar A., McCray, Richard, Garnavich, Peter M., Challis, Peter M., ...
We report and interpret HST/STIS long-slit observations of the optical and ultraviolet (1150 - 10270 Angstrom) emission-line spectra of the rapidly brightening Spot 1 on the equatorial ring of SN...
A Comparative Study of the Absolute-Magnitude Distributions of Supernovae (2001)
Richardson, Dean, Branch, David, Casebeer, Darrin, Millard, Jennifer, Thomas, R. C., Baron, E.
The Asiago Supernova Catalog is used to carry out a comparative study of supernova absolute-magnitude distributions. An overview of the absolute magnitudes of the supernovae in the current...
Optical Spectra of Supernovae (2001)
Branch, David, Baron, E., Jeffery, David J.
Supernova flux and polarization spectra bring vital information on the geometry, physical conditions, and composition structure of the ejected matter. For some supernovae the circumstellar matter is...
A complete analytic inversion of supernova lines in the Sobolev approximation (2001)
Kasen, Daniel, Branch, David, Baron, E., Jeffery, David
We show that the shape of P-Cygni line profiles of photospheric phase supernova can be analytically inverted to extract both the optical depth and source function of the line -- i.e. all the physical...
Coping with Type Ia Supernova "Evolution" When Probing the Nature of the Dark Energy (2001)
Branch, David, Perlmutter, Saul, Baron, E., Nugent, Peter
Observations of high-redshift Type Ia supernovae (SNe Ia) have provided strong evidence that the dark energy is real, and making further accurate observations of high-redshift SNe Ia is the most...
A Complete Analytic Inversion of Supernova Lines in the Sobolev Approximation (2001)
Kasen, Daniel, Branch, David, Baron, E., Jeffery, David
We show that the shape of P-Cygni line profiles of photospheric phase supernova can be analytically inverted to extract both the optical depth and source function of the line -- i.e. all the physical...
Spectral Consequences of Deviation from Spherical Composition Symmetry in Type Ia Supernovae (2001)
Thomas, R. C., Kasen, Daniel, Branch, David, Baron, E.
We investigate the prospects for constraining the maximum scale of clumping in composition that is consistent with observed Type Ia supernova flux spectra. Synthetic spectra generated without purely...
Direct Analysis of Spectra of Type Ib Supernovae (2001)
Synthetic spectra generated with the parameterized supernova synthetic-spectrum code SYNOW are compared to photospheric-phase spectra of Type Ib supernovae (SNe Ib). Although the synthetic spectra...
The Luminosity of SN 1999by in NGC 2841 and the Nature of `Peculiar' Type Ia Supernovae (2001)
Garnavich, Peter M., Bonanos, Alceste Z., Krisciunas, Kevin, Jha, Saurabh, Kirshner, Robert P., Schlegel, Eric M., ...
We present UBVRIJHK photometry and optical spectroscopy of the so-called 'peculiar' Type Ia supernova 1999by in NGC 2841. The observations began one week before visual maximum light which is...
NLTE Synthetic Spectral Fits to the Type Ia Supernova 1994D in NGC 4526 (2001)
Lentz, Eric J., Baron, E., Branch, David, Hauschildt, Peter H.
We have fit the normal, well observed, Type Ia Supernova (SN Ia) SN 1994D with non-LTE spectra of the deflagration model W7. We find that well before maximum luminosity W7 fits the optical spectra of...
Nickel Mixing in the Outer Layers of SN 1987A (2001)
Mitchell, Robert C., Baron, E., Branch, David, Lundqvist, Peter, Blinnikov, Sergei, Hauschildt, Peter H., ...
Supernova 1987A remains the most well-observed and well-studied supernova to date. Observations produced excellent broad-band photometric and spectroscopic coverage over a wide wavelength range at...
Type Ia Supernovae: Toward the Standard Model? (2000)
In this short review I suggest that recent developments support the conjecture that Type Ia supernovae (SNe Ia) are the complete disruptions of Chandrasekhar-mass carbon-oxygen white dwarfs in...
Preliminary Spectral Analysis of the Type II Supernova 1999em (2000)
Baron, E., Branch, David, Hauschildt, Peter H., Filippenko, Alexei V., Kirshner, R. P., Challis, P. M., ...
We have calculated fast direct spectral model fits to two early-time spectra of the Type-II plateau SN 1999em, using the SYNOW synthetic spectrum code. The first is an extremely early blue optical...
Lentz, Eric J., Baron, E., Lundqvist, Peter, Branch, David, Hauschildt, Peter H., Fransson, Claes, ...
We present spectral analysis of early observations of the Type IIn supernova 1998S using the general non-local thermodynamic equilibrium atmosphere code \tt PHOENIX}. We model both the underlying...
On the Spectroscopic Diversity of Type Ia Supernovae (2000)
Hatano, Kazuhito, Branch, David, Lentz, Eric J., Baron, E., Filippenko, Alexei V., Garnavich, Peter M.
A comparison of the ratio of the depths of two absorption features in the spectra of TypeIa supernovae (SNe Ia) near the time of maximum brightness with the blueshift of the deep red Si II absorption...
SN 1984A and Delayed Detonation Models of Type Ia Supernovae (2000)
Lentz, Eric J., Baron, E., Branch, David, Hauschildt, P. H.
SN 1984A shows unusually large expansion velocities in lines from freshly synthesized material, relative to typical Type Ia Supernovae (SNe Ia). SN 1984A is an example of a group of SNe Ia which have...
Spectral Models of the Type Ic SN 1994I in M51 (1999)
Baron, E., Branch, David, Hauschildt, Peter H., Filippenko, Alexei V., Kirshner, R. P.
We present detailed non-local thermodynamic equilibrium (NLTE) synthetic spectra for comparison with a time series of observed optical spectra of the Type Ic supernova 1994I which occurred in M51....
Metallicity Effects in NLTE Model Atmospheres of Type Ia Supernovae (1999)
Lentz, Eric J., Baron, E., Branch, David, Hauschildt, Peter H., Nugent, Peter E.
We have calculated a grid of photospheric phase atmospheres of Type Ia supernovae (SNe Ia) with metallicities from ten times to one thirtieth the solar metallicity in the C+O layer of the...
Preliminary Spectral Analysis of the Type II Supernova 1999em (1999)
E. Baron, David Branch, Peter H. Hauschildt
We have calculated fast direct spectral model fits to two early spectra of SN 1999em, using the SYNOW synthetic spectrum code. The first is an extremely early blue optical spectrum and the second a...
Monte Carlo Simulation of the Galactic Al-26 Gamma-Ray Map (1998)
Lentz, Eric J., Branch, David, Baron, E.
The observed map of 1.809 MeV gamma-rays from radioactive Al-26 (Oberlack et al, 1996) shows clear evidence of Galactic plane origin with an uneven distribution. We have simulated the map using a...
New Insight into the Spatial Distribution of Novae in M31 (1997)
Hatano, Kazuhito, Branch, David, Fisher, Adam, Starrfield, Sumner
We use a Monte Carlo technique together with a simple model for the distribution of dust in M31 to investigate the observability and spatial distribution of classical novae in M31.
Type Ia Supernovae as Extragalactic Distance Indicators (1997)
David Branch, Peter Nugent, Adam Fisher
Because Type Ia supernovae (SNe Ia) are not perfect standard candles, it is important to be able to use distance--independent observables (DIOs) to define subsets of SNe Ia that are "nearly...
Low Hubble Constant from Type Ia Supernovae by van den Bergh's Method (1996)
Branch, David, Fisher, Adam, Baron, E., Nugent, Peter
An interesting way to calibrate the absolute magnitudes of remote Type Ia supernovae (SNe Ia) that are well out in the Hubble flow, and thus determine the value of the Hubble constant, H_0, has been...
Type Ia Supernovae as Extragalactic Distance Indicators (1996)
Branch, David, Nugent, Peter, Fisher, Adam
Because Type Ia supernovae (SNe Ia) are not perfect standard candles, it is important to be able to use distance-independent observables (DIOs) to define subsets of SNe Ia that are ``nearly standard...
Branch, David, Romanishin, W., Baron, E.
Statistical connections between the properties of Type Ia supernovae (SNe Ia) and the B--V colors of their parent galaxies are established. Compared to SNe Ia in blue galaxies [B-V$\la$0.75], SNe Ia...
Evidence for a Spectroscopic Sequence Among SNe Ia (1995)
Nugent, Peter, Phillips, Mark, Baron, E., Branch, David, Hauschildt, Peter
In this Letter we present evidence for a spectral sequence among Type Ia supernovae (SNe Ia). The sequence is based on the systematic variation of several features seen in the near-maximum light...