papers

Publications (149)

astro-ph.HE2018

Shedding light on the Type Ia supernova extinction puzzle: dust location found

M. Bulla, A. Goobar, S. Dhawan

The colour evolution of reddened Type Ia supernovae can place strong constraints on the location of dust and help address the question of whether the observed extinction stems from…

astro-ph2006

SN 2004aw: Confirming Diversity of Type Ic Supernovae

S. Taubenberger, A. Pastorello, P. A. Mazzali +24

Optical and near-infrared observations of the Type Ic supernova (SN) 2004aw are presented, obtained from day -3 to day +413 with respect to the B-band maximum. The photometric evol…

astro-ph2008

Discovery of an Unusual Optical Transient with the Hubble Space Telescope

K. Barbary, K. S. Dawson, K. Tokita +27

We present observations of SCP 06F6, an unusual optical transient discovered during the Hubble Space Telescope Cluster Supernova Survey. The transient brightened over a period of ~…

astro-ph.HE2020

The Spectacular Ultraviolet Flash From the Peculiar Type Ia Supernova 2019yvq

A. A. Miller, M. R. Magee, A. Polin +42

Early observations of Type Ia supernovae (SNeIa) provide essential clues for understanding the progenitor system that gave rise to the terminal thermonuclear explosion. We pres…

astro-ph.SR2011

Multi-epoch high-resolution spectroscopy of SN2011fe - Linking the progenitor to its environment

F. Patat, M. A. Cordiner, N. L. J. Cox +10

This study attempts to establish a link between the reasonably well known nature of the progenitor of SN2011fe and its surrounding environment. This is done with the aim of enablin…

astro-ph.HE2016

Detectability of compact binary merger macronovae

S. Rosswog, U. Feindt, O. Korobkin +4

We study the optical and near-infrared luminosities and detectability of radioactively powered electromagnetic transients ('macronovae') occuring in the aftermath of binary neutron…

astro-ph.CO2020

Lens modelling of the strongly lensed Type Ia supernova iPTF16geu

E. Mörtsell, J. Johansson, S. Dhawan +3

In 2016, the first strongly lensed Type Ia supernova, iPTF16geu at redshift with four resolved images arranged symmetrically around the lens galaxy at , was dis…

astro-ph.CO2021

The Zwicky Transient Facility Type Ia supernova survey: first data release and results

S. Dhawan, A. Goobar, M. Smith +17

Type Ia supernovae (SNe~Ia) in the nearby Hubble flow are excellent distance indicators in cosmology. The Zwicky Transient Facility (ZTF) has observed a large sample of supernovae…

astro-ph2008

Improved Cosmological Constraints from New, Old and Combined Supernova Datasets

M. Kowalski, D. Rubin, G. Aldering +67

We present a new compilation of Type Ia supernovae (SNe Ia), a new dataset of low-redshift nearby-Hubble-flow SNe and new analysis procedures to work with these heterogeneous compi…

astro-ph2005

The Supernova Legacy Survey: Measurement of Omega_M, Omega_Lambda and w from the First Year Data Set

P. Astier, J. Guy, N. Regnault +39

We present distance measurements to 71 high redshift type Ia supernovae discovered during the first year of the 5-year Supernova Legacy Survey (SNLS). These events were detected an…

astro-ph.HE2025

ZTF SN Ia DR2: The diversity and relative rates of the thermonuclear SN population

G. Dimitriadis, U. Burgaz, M. Deckers +28

The Zwicky Transient Facility SN Ia Data Release 2 (ZTF SN Ia DR2) contains more than 3,000 Type Ia supernovae (SNe Ia), providing the largest homogeneous low-redshift sample of SN…

astro-ph.HE2025

Candidate strongly lensed type Ia supernovae in the Zwicky Transient Facility archive

A. Townsend, J. Nordin, A. Sagués Carracedo +61

Gravitationally lensed type Ia supernovae (glSNe Ia) are unique astronomical tools that can be used to study cosmological parameters, distributions of dark matter, the astrophysics…

astro-ph1995

A Supernova at z = 0.458 and Implications for Measuring the Cosmological Deceleration

S. Perlmutter, C. R. Pennypacker, G. Goldhaber +20

We have begun a program to discover high-redshift supernovae ( 0.25--0.5), and study them with follow-up photometry and spectroscopy. We report here our first discovery,…

astro-ph.CO2020

Cosmological model insensitivity of local from the Cepheid distance ladder

S. Dhawan, D. Brout, D. Scolnic +3

The observed tension ( difference) between the local distance ladder measurement of the Hubble constant, , and its value inferred from the cosmic microwave backgroun…

astro-ph2003

Supernova 2002bo: inadequacy of the single parameter description

S. Benetti, P. Meikle, M. Stehle +15

We present optical/near-infrared photometry and spectra of the type Ia SN 2002bo spanning epochs from -13 days before maximum B-band light to +102 days after. The pre-maximum optic…

astro-ph2007

The Sloan Digital Sky Survey-II Supernova Survey: Technical Summary

Joshua A. Frieman, B. Bassett, A. Becker +98

The Sloan Digital Sky Survey-II (SDSS-II) has embarked on a multi-year project to identify and measure light curves for intermediate-redshift (0.05 < z < 0.35) Type Ia supernovae (…

astro-ph.HE2024

Detectability and Characterisation of Strongly Lensed Supernova Lightcurves in the Zwicky Transient Facility

A. Sagués Carracedo, A. Goobar, E. Mörtsell +7

The Zwicky Transient Facility (ZTF) was expected to detect more than one strong gravitationally-lensed supernova (glSN) per year, but only one event was identified in the first fou…

astro-ph1996

The Type Ia Supernova Rate at z

R. Pain, I. M. Hook, S. Deustua +17

We present the first measurement of the rate of Type Ia supernovae at high redshift. The result is derived using a large subset of data from the Supernova Cosmology Project. Three…

astro-ph2007

Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study

G. Garavini, G. Folatelli, S. Nobili +44

We develop a method to measure the strength of the absorption features in Type Ia supernova (SN Ia) spectra and use it to make a quantitative comparison between the spectra of Type…

astro-ph1997

Implications For The Hubble Constant from the First Seven Supernovae at z >= 0.35

The Supernova Cosmology Project, :, A. G. Kim +23

The Supernova Cosmology Project has discovered over twenty-eight supernovae (SNe) at 0.35 <z < 0.65 in an ongoing program that uses Type Ia SNe as high-redshift distance indicators…

astro-ph2007

A New Determination of the High Redshift Type Ia Supernova Rates with the Hubble Space Telescope Advanced Camera for Surveys

N. Kuznetsova, K. Barbary, B. Connolly +27

We present a new measurement of the volumetric rate of Type Ia supernova up to a redshift of 1.7, using the Hubble Space Telescope (HST) GOODS data combined with an additional HST…

astro-ph.HE2017

Color Me Intrigued: the Discovery of iPTF 16fnm, a Supernova 2002cx-like Object

A. A. Miller, M. M. Kasliwal, Y. Cao +13

Modern wide-field, optical time-domain surveys must solve a basic optimization problem: maximize the number of transient discoveries or minimize the follow-up needed for the new di…

astro-ph.CO2017

iPTF16geu: A multiply imaged, gravitationally lensed type Ia supernova

A. Goobar, R. Amanullah, S. R. Kulkarni +31

We report the discovery of a multiply-imaged gravitationally lensed Type Ia supernova, iPTF16geu (SN 2016geu), at redshift . This phenomenon could be identified because th…

astro-ph.HE2018

The first direct double neutron star merger detection: implications for cosmic nucleosynthesis

S. Rosswog, J. Sollerman, U. Feindt +4

The astrophysical r-process site where about half of the elements heavier than iron are produced has been a puzzle for several decades. Here we discuss the role of neutron star mer…

astro-ph2008

Light curves of five type Ia supernovae at intermediate redshift

R. Amanullah, V. Stanishev, A. Goobar +14

We present multi-band light curves and distances for five type Ia supernovae at intermediate redshifts, 0.18<z<0.27. Three telescopes on the Canary Island of La Palma, INT, NOT and…

astro-ph.CO2009

Near-IR search for lensed supernovae behind galaxy clusters: I. Observations and transient detection efficiency

V. Stanishev, A. Goobar, K. Paech +11

Massive galaxy clusters at intermediate redshift can magnify the flux of distant background sources by several magnitudes and we exploit this effect to search for lensed distant su…

astro-ph2005

Restframe I-band Hubble diagram for type Ia supernovae up to redshift z ~0.5

The Supernova Cosmology Project, :, S. Nobili +35

We present a novel technique for fitting restframe I-band light curves on a data set of 42 Type Ia supernovae (SNe Ia). Using the result of the fit, we construct a Hubble diagram w…

astro-ph.HE2017

Estimating dust distances to Type Ia supernovae from colour excess time-evolution

M. Bulla, A. Goobar, R. Amanullah +2

We present a new technique to infer dust locations towards reddened Type Ia supernovae and to help discriminate between an interstellar and a circumstellar origin for the observed…

astro-ph.HE2021

Detectability of kilonovae in optical surveys: - examination of the LVC O3 run follow-up

A. Sagués Carracedo, M. Bulla, U. Feindt +1

The detection of the binary neutron star merger GW170817 and the associated electromagnetic (EM) counterpart, the "kilonova" (kN) AT2017gfo, opened a new era in multi-messenger ast…

astro-ph.HE2018

Early Observations of the Type Ia Supernova iPTF 16abc: A Case of Interaction with Nearby, Unbound Material and/or Strong Ejecta Mixing

A. A. Miller, Y. Cao, A. L. Piro +19

Early observations of Type Ia supernovae (SNe Ia) provide a unique probe of their progenitor systems and explosion physics. Here we report the intermediate Palomar Transient Factor…

astro-ph.HE2015

No trace of a single-degenerate companion in late spectra of SNe 2011fe and 2014J

P. Lundqvist, A. Nyholm, F. Taddia +9

Left-over, ablated material from a possible non-degenerate companion can reveal itself after about one year in spectra of Type Ia SNe (SNe Ia). We have searched for such material i…

astro-ph.CO2009

An Intensive HST Survey for z>1 Supernovae by Targeting Galaxy Clusters

K. S. Dawson, G. Aldering, R. Amanullah +57

We present a new survey strategy to discover and study high redshift Type Ia supernovae (SNe Ia) using the Hubble Space Telescope (HST). By targeting massive galaxy clusters at 0.9…

astro-ph.CO2013

Precision Measurement of The Most Distant Spectroscopically Confirmed Supernova Ia with the Hubble Space Telescope

D. Rubin, R. A. Knop, E. Rykoff +25

We report the discovery of a redshift 1.71 supernova in the GOODS North field. The Hubble Space Telescope (HST) ACS spectrum has almost negligible contamination from the host or ne…

astro-ph.HE2018

iPTF16abc and the population of Type Ia supernovae: Comparing the photospheric, transitional and nebular phases

S. Dhawan, M. Bulla, A. Goobar +6

Key information about the progenitor system and the explosion mechanism of Type Ia supernovae (SNe~Ia) can be obtained from early observations, within a few days from explosion. iP…

astro-ph.GA2025

ZTF SN Ia DR2 follow-up: Exploring the origin of the Type Ia supernova host galaxy step through Si II velocities

U. Burgaz, K. Maguire, L. Galbany +18

The relationship between Type Ia supernovae (SNe Ia) and their host galaxy stellar masses is well documented. In particular, Hubble residuals display a luminosity shift based on ho…

astro-ph.GA2020

See Change: VLT spectroscopy of a sample of high-redshift Type Ia supernova host galaxies

S. C. Williams, I. M. Hook, B. Hayden +9

The Supernova Cosmology Project has conducted the `See Change' programme, aimed at discovering and observing high-redshift (1.13 z 1.75) Type Ia supernovae (SNe Ia).…

astro-ph1998

Cosmology from Type Ia Supernovae

S. Perlmutter, G. Aldering, S. Deustua +25

This presentation reports on first evidence for a low-mass-density/positive-cosmological-constant universe that will expand forever, based on observations of a set of 40 high-redsh…

astro-ph2007

The early spectral evolution of SN 2004dt

G. Altavilla, M. Stehle, P. Ruiz-Lapuente +18

Aims. We study the optical spectroscopic properties of Type Ia Supernova (SN Ia) 2004dt, focusing our attention on the early epochs. Methods. Observation triggered soon after the S…

astro-ph2004

Supernova / Acceleration Probe: A Satellite Experiment to Study the Nature of the Dark Energy

SNAP Collaboration, G. Aldering, W. Althouse +109

The Supernova / Acceleration Probe (SNAP) is a proposed space-based experiment designed to study the dark energy and alternative explanations of the acceleration of the Universe's…

astro-ph2009

Near-IR Search for Lensed Supernovae Behind Galaxy Clusters - II. First Detection and Future Prospects

A. Goobar, K. Paech, V. Stanishev +11

Powerful gravitational telescopes in the form of massive galaxy clusters can be used to enhance the light collecting power over a limited field of view by about an order of magnitu…

astro-ph.HE2017

Testing for redshift evolution of Type Ia supernovae using the strongly lensed PS1-10afx at

T. Petrushevska, R. Amanullah, M. Bulla +4

The light from distant supernovae (SNe) can be magnified through gravitational lensing when a foreground galaxy is located along the line of sight. This line-up allows for detailed…

astro-ph2001

Determining the fraction of compact objects in the Universe using supernova observations

E. Moertsell, A. Goobar, L. Bergstrom

We investigate the possibility to determine the fraction of compact objects in the Universe by studying gravitational lensing effects on Type Ia supernova observations. Using simul…

astro-ph.SR2012

SN 2006oz: rise of a super-luminous supernova observed by the SDSS-II SN Survey

G. Leloudas, E. Chatzopoulos, B. Dilday +21

We study SN 2006oz, a newly-recognized member of the class of H-poor, super-luminous supernovae. We present multi-color light curves from the SDSS-II SN Survey, that cover the rise…

astro-ph.HE2021

Supernova Siblings and their Parent Galaxies in the Zwicky Transient Facility Bright Transient Surve

M. L. Graham, C. Fremling, D. A. Perley +19

Supernova (SN) siblings -- two or more SNe in the same parent galaxy -- are useful tools for exploring progenitor stellar populations as well as properties of the host galaxies suc…

astro-ph.SR2016

An Intermediate Type Ia Supernova Between Normal And Super-Chandrasekhar

Yi Cao, J. Johansson, Peter E. Nugent +14

In this paper, we report observations of a peculiar Type Ia supernova iPTF13asv (a.k.a., SN2013cv) from the onset of the explosion to months after its peak. The early-phase spectra…

astro-ph.HE2021

The luminous and rapidly evolving SN 2018bcc: Clues toward the origin of Type Ibn SNe from the Zwicky Transient Facility

E. Karamehmetoglu, C. Fransson, J. Sollerman +20

Supernovae (SNe) Type Ibn are rapidly evolving and bright (M ) transients interacting with He-rich circumstellar material (CSM). SN 2018bcc, detected by th…

astro-ph.CO2025

ZTF SN Ia DR2: Colour standardisation of Type Ia Supernovae and its dependence on environment

M. Ginolin, M. Rigault, Y. Copin +37

As type Ia supernova (SN Ia) cosmology transitions from a statistics-dominated to a systematics-dominated era, it is crucial to understand the remaining unexplained uncertainties t…

astro-ph.HE2019

Constraining the observer angle of the kilonova AT2017gfo associated with GW170817: Implications for the Hubble constant

S. Dhawan, M. Bulla, A. Goobar +2

There is a strong degeneracy between the luminosity distance () and the observer viewing angle (; hereafter viewing angle) of the gravitational wave (GW) source…

astro-ph.HE2024

ZTF SN Ia DR2: The secondary maximum in Type Ia supernovae

M. Deckers, K. Maguire, L. Shingles +24

Type Ia supernova (SN Ia) light curves have a secondary maximum that exists in the , , and near-infrared filters. The secondary maximum is relatively weak in the band, bu…

astro-ph.IM2026

Photometric classification of supernovae detected by the Zwicky Transient Facility using noise augmentation

A. Townsend, J. Nordin, M. Kowalski +27

Modern time-domain surveys, such as the Zwicky Transient Facility (ZTF), detect far more extragalactic transients than can be spectroscopically classified. Photometric classificati…

astro-ph.HE2019

The Zwicky Transient Facility Bright Transient Survey I: Spectroscopic Classification and the Redshift Completeness of Local Galaxy Catalogs

U. C. Fremling, A. A. Miller, Y. Sharma +37

The Zwicky Transient Facility (ZTF) is performing a three-day cadence survey of the visible Northern sky (~3). The transient candidates found in this survey are announced via p…

astro-ph.HE2024

ZTF SN Ia DR2: The spectral diversity of Type Ia supernovae in a volume-limited sample

U. Burgaz, K. Maguire, G. Dimitriadis +30

More than 3000 spectroscopically confirmed Type Ia supernovae (SNe Ia) are presented in the Zwicky Transient Facility SN Ia Data Release 2 (ZTF DR2). In this paper, we detail the s…

astro-ph.CO2009

Characterizing the Properties of Clusters of Galaxies as a Function of Luminosity and Redshift

K. Andersson, J. R. Peterson, G. Madejski +1

We report the application of a new Monte Carlo method, Smoothed Particle Inference (SPI, described in a pair of companion papers), towards analysis and interpretation of X-ray obse…

astro-ph.CO2025

ZTF SNe Ia DR2: Towards cosmology-grade ZTF supernova light curves using scene modeling photometry

L. Lacroix, N. Regnault, T. de Jaeger +36

The Zwicky Transient Facility (ZTF) is conducting a wide-field survey of the northern sky in three optical bands and the collaboration cosmology working group has released 3628 spe…

astro-ph.GA2024

ZTF SN Ia DR2: An environmental study of Type Ia supernovae using host galaxy image decomposition

R. Senzel, K. Maguire, U. Burgaz +18

The second data release of Type Ia supernovae (SNe Ia) observed by the Zwicky Transient Facility has provided a homogeneous sample of 3628 SNe Ia with photometric and spectral info…

astro-ph.HE2018

Carnegie Supernova Project-II: Extending the Near-Infrared Hubble Diagram for Type Ia Supernovae to

M. M. Phillips, Carlos Contreras, E. Y. Hsiao +41

The Carnegie Supernova Project-II (CSP-II) was an NSF-funded, four-year program to obtain optical and near-infrared observations of a "Cosmology" sample of Type Ia supern…

astro-ph.CO2024

ZTF SN Ia DR2: Exploring SN Ia properties in the vicinity of under-dense environments

M. Aubert, P. Rosnet, B. Popovic +29

The unprecedented statistics of detected Type Ia supernovae (SNe Ia) brought by the Zwicky Transient Facility enables us to probe the impact of the Large-Scale Structure on the pro…

astro-ph.HE2018

Delayed Circumstellar Interaction for Type Ia SN 2015cp Revealed by an HST Ultraviolet Imaging Survey

M. L. Graham, C. E. Harris, P. E. Nugent +11

The nature and role of the binary companion of carbon-oxygen white dwarf stars that explode as Type Ia supernovae (SNe Ia) are not yet fully understood. Past detections of circumst…

astro-ph.GA2014

The rise of SN2014J in the nearby galaxy M82

A. Goobar, J. Johansson, R. Amanullah +31

We report on the discovery of SN2014J in the nearby galaxy M82. Given its proximity, it offers the best opportunity to date to study a thermonuclear supernova over a wide range of…

astro-ph.CO2024

Optical and near-infrared photometry of 94 type II supernovae from the Carnegie Supernova Project

J. P. Anderson, C. Contreras, M. D. Stritzinger +43

Type II supernovae (SNeII) mark the endpoint in the lives of hydrogen-rich massive stars. Their large explosion energies and luminosities allow us to measure distances, metalliciti…

astro-ph.CO2024

ZTF SN Ia DR2: Simulations and volume limited sample

M. Amenouche, M. Smith, P. Rosnet +27

Type Ia supernovae (SNe Ia) constitute an historical probe to derive cosmological parameters through the fit of the Hubble-Lemaître diagram, i.e. SN Ia distance modulus versus the…

astro-ph.HE2021

AT 2019avd: A novel addition to the diverse population of nuclear transients

A. Malyali, A. Rau, A. Merloni +29

We report on SRG/eROSITA, ZTF, ASAS-SN, Las Cumbres, NEOWISE-R, and Swift XRT/UVOT observations of the unique ongoing event AT 2019avd, located in the nucleus of a previously inact…

astro-ph.CO2025

ZTF SN Ia DR2: Environmental dependencies of stretch and luminosity of a volume limited sample of 1,000 Type Ia Supernovae

M. Ginolin, M. Rigault, M. Smith +43

To get distances, Type Ia Supernovae magnitudes are corrected for their correlation with lightcurve width and colour. Here we investigate how this standardisation is affected by th…

astro-ph.HE2018

R-band light-curve properties of Type Ia supernovae from the (intermediate) Palomar Transient Factory

S. Papadogiannakis, A. Goobar, R. Amanullah +15

We present the best 265 sampled R-band light curves of spectroscopically identified Type Ia supernovae (SNe) from the Palomar Transient Factory (PTF; 2009-2012) survey and the inte…

astro-ph1997

Discovery of a Supernova Explosion at Half the Age of the Universe and its Cosmological Implications

S. Perlmutter, G. Aldering, M. Della Valle +20

The ultimate fate of the universe, infinite expansion or a big crunch, can be determined by measuring the redshifts, apparent brightnesses, and intrinsic luminosities of very dista…

astro-ph2005

High-Velocity Features: a ubiquitous property of Type Ia SNe

P. A. Mazzali, S. Benetti, G. Altavilla +26

Evidence of high-velocity features such as those seen in the near-maximum spectra of some Type Ia Supernovae (eg SN 2000cx) has been searched for in the available SNIa spectra obse…

astro-ph.CO2025

ZTF SN Ia DR2: Improved SN Ia colors through expanded dimensionality with SALT3+

W. D. Kenworthy, A. Goobar, D. O. Jones +24

Type Ia supernovae (SNe Ia) are a key probe in modern cosmology, as they can be used to measure luminosity distances at gigaparsec scales. Models of their light-curves are used to…

astro-ph.GA2021

Near-IR Type Ia SN distances: host galaxy extinction and mass-step corrections revisited

J. Johansson, S. B. Cenko, O. D. Fox +17

We present optical and near-infrared (NIR, -band) observations of 42 Type Ia supernovae (SNe Ia) discovered by the untargeted intermediate Palomar Transient Factory (iPTF) sur…

astro-ph.SR2015

Strong Ultraviolet Pulse From a Newborn Type Ia Supernova

Yi Cao, S. R. Kulkarni, D. Andrew Howell +19

Type Ia supernovae are destructive explosions of carbon oxygen white dwarfs. Although they are used empirically to measure cosmological distances, the nature of their progenitors r…

astro-ph2004

No evidence for Dark Energy Metamorphosis ?

J. Jonsson, A. Goobar, R. Amanullah +1

Recent attempts to fit Type Ia supernova data by modeling the dark energy density as a truncated Taylor series have suggested the possibility of metamorphosis, i.e., a rapidly evol…

astro-ph.HE2014

Constraints on the origin of the first light from SN2014J

A. Goobar, M. Kromer, R. Siverd +6

We study the very early lightcurve of supernova 2014J (SN 2014J) using the high-cadence broad-band imaging data obtained by the Kilodegree Extremely Little Telescope (KELT), which…

astro-ph1996

K Corrections For Type Ia Supernovae and a Test for Spatial Variation of the Hubble Constant

A. Kim, S. Deustua, S. Gabi +23

Cross-filter K corrections for a sample of "normal" Type Ia supernovae (SNe) have been calculated for a range of epochs. With appropriate filter choices, the combined statistical a…

astro-ph.CO2024

ZTF SN Ia DR2: Study of Type Ia Supernova lightcurve fits

M. Rigault, M. Smith, N. Regnault +34

Type Ia supernova (SN Ia) cosmology relies on the estimation of lightcurve parameters to derive precision distances that leads to the estimation of cosmological parameters. The emp…

astro-ph.HE2024

ZTF SN Ia DR2: Properties of the low-mass host galaxies of Type Ia supernovae in a volume-limited sample

U. Burgaz, K. Maguire, G. Dimitriadis +25

In this study, we explore the characteristics of `low-mass' () and `intermediate-mass' () host galaxies o…

astro-ph2007

ESC observations of SN 2005cf: II. Optical Spectroscopy and the high velocity features

G. Garavini, S. Nobili, S. Taubenberger +11

The ESC-RTN optical spectroscopy data-set for SN 2005cf is presented and analyzed. The observations range from -11.6 and +77.3 days with respect to B-band maximum light. The evolut…

astro-ph.CO2026

Study of the anisotropy of cosmic expansion on ZTF type Iasupernovae simulations

C. Barjou-Delayre, P. Rosnet, C. Ravoux +29

The cosmological principle assumes the isotropy of the Universe at large scales. It is a foundational assumption in the CDM model, which is the current standard model of cosmol…

astro-ph.HE2016

The peculiar Type Ia supernova iPTF14atg: Chandrasekhar-mass explosion or violent merger?

M. Kromer, C. Fremling, R. Pakmor +11

iPTF14atg, a subluminous peculiar Type Ia supernova (SN Ia) similar to SN 2002es, is the first SN Ia for which a strong UV flash was observed in the early-time light curves. This h…

astro-ph2001

Timescale Stretch Parameterization of Type Ia Supernova B-band Light Curves

G. Goldhaber, D. E. Groom, A. Kim +24

R-band intensity measurements along the light curve of Type Ia supernovae discovered by the Supernova Cosmology Project (SCP) are fitted in brightness to templates allowing a free…

astro-ph.SR2015

Strong near-infrared carbon in the Type Ia supernova iPTF13ebh

E. Y. Hsiao, C. R. Burns, C. Contreras +51

We present near-infrared (NIR) time-series spectroscopy, as well as complementary ultraviolet (UV), optical, and NIR data, of the Type Ia supernova (SN Ia) iPTF13ebh, which was dis…

astro-ph.CO2011

Evidence for a correlation between the Si II 4000 width and Type Ia supernova color

J. Nordin, L. Ostman, A. Goobar +8

We study the pseudo equivalent width of the Si II 4000 feature of Type Ia supernovae in the redshift range 0.0024 < z < 0.634. We find that this spectral indicator correlates with…

astro-ph2002

The distant Type Ia supernova rate

R. Pain, S. Fabbro, M. Sullivan +26

We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample, which su…

astro-ph2004

Spectroscopic confirmation of high-redshift supernovae with the ESO VLT

C. Lidman, D. A. Howell, G. Folatelli +44

We present VLT FORS1 and FORS2 spectra of 39 candidate high-redshift supernovae that were discovered as part of a cosmological study using Type Ia supernovae (SNe Ia) over a wide r…

astro-ph2002

SNOC: a Monte-Carlo simulation package for high-z supernova observations

A. Goobar, E. Mortsell, R. Amanullah +3

We present a Monte-Carlo package for simulation of high-redshift supernova data, SNOC. Optical and near-infrared photons from supernovae are ray-traced over cosmological distances…

astro-ph.GA2018

Searching for supernovae in the multiply-imaged galaxies behind the gravitational telescope A370

T. Petrushevska, A. Goobar, D. J. Lagattuta +7

Strong lensing by massive galaxy clusters can provide magnification of the flux and even multiple images of the galaxies that lie behind them. This phenomenon facilitates observati…

astro-ph.SR2025

Euclid: Quick Data Release (Q1) -- Photometric studies of known transients

C. Duffy, E. Cappellaro, M. T. Botticella +174

We report on serendipitous Euclid observations of previously known transients, using the Euclid Q1 data release. By cross-matching with the Transient Name Server (TNS) we identify…

astro-ph.CO2019

Prospects for observing strongly lensed supernovae behind Hubble Frontier Fields galaxy clusters with the James Webb Space Telescope

T. Petrushevska, T. Okamura, R. Kawamata +3

Measuring time delays from strongly lensed supernovae (SNe) is emerging as a novel and independent tool for estimating the Hubble constant . This is very important given the…

astro-ph.CO2010

Spectra and Light Curves of Six Type Ia Supernovae at 0.511 < z < 1.12 and the Union2 Compilation

R. Amanullah, C. Lidman, D. Rubin +42

We report on work to increase the number of well-measured Type Ia supernovae (SNe Ia) at high redshifts. Light curves, including high signal-to-noise HST data, and spectra of six S…

astro-ph2006

Type Ia SNe along redshift: the R(Si II) ratio and the expansion velocities in intermediate z supernovae

G. Altavilla, P. Ruiz-Lapuente, A. Balastegui +17

We study intermediate--z SNe Ia using the empirical physical diagrams which enable to learn about those SNe explosions. This information can be very useful to reduce systematic unc…

astro-ph2001

Supernovae and the Nature of the Dark Energy

M. Goliath, R. Amanullah, P. Astier +2

The use of Type Ia supernovae as calibrated standard candles is one of the most powerful tools to study the expansion history of the universe and thereby its energy components. Whi…

astro-ph2006

The Peculiar Type Ia Supernova 2005hk

V. Stanishev, S. Taubenberger, G. Blanc +15

We present a preliminary analysis of an extensive set of optical observations of the Type Ia SN 2005hk. We show that the evolution of SN 2005hk closely follows that of the peculiar…

astro-ph.HE2017

Spitzer observations of SN 2014J and properties of mid-IR emission in Type Ia supernovae

J. Johansson, A. Goobar, M. M. Kasliwal +13

SN 2014J in M82 is the closest Type Ia supernova (SN Ia) in decades. The proximity allows for detailed studies of supernova physics and provides insights into the circumstellar and…

astro-ph.CO2026

The Dark Energy Survey Supernova Program: A Reanalysis Of Cosmology Results And Evidence For Evolving Dark Energy With An Updated Type Ia Supernova Calibration

B. Popovic, P. Shah, W. D. Kenworthy +80

We present improved cosmological constraints from a re-analysis of the Dark Energy Survey (DES) 5-year sample of Type Ia supernovae (DES-SN5YR). This re-analysis includes an improv…

astro-ph.CO2011

The Hubble Space Telescope Cluster Supernova Survey: VI. The Volumetric Type Ia Supernova Rate

K. Barbary, G. Aldering, R. Amanullah +40

We present a measurement of the volumetric Type Ia supernova (SN Ia) rate out to z ~ 1.6 from the Hubble Space Telescope Cluster Supernova Survey. In observations spanning 189 orbi…

astro-ph2003

New Constraints on , , and w from an Independent Set of Eleven High-Redshift Supernovae Observed with HST

R. A. Knop, G. Aldering, R. Amanullah +45

We report measurements of , , and w from eleven supernovae at z=0.36-0.86 with high-quality lightcurves measured using WFPC-2 on the HST. This is an independent set of…

astro-ph.CO2024

ZTF SN Ia DR2: Evidence of Changing Dust Distributions With Redshift Using Type Ia Supernovae

B. Popovic, M. Rigault, M. Smith +29

Type Ia supernova (SNIa) are excellent probes of local distance, and the increasing sample sizes of SNIa have driven an increased need to study the associated systematic uncertaint…

astro-ph1996

Observation of Cosmological Time Dilation using Type Ia Supernovae as Clocks

G. Goldhaber, S. Deustua, S. Gabi +23

This work is based on the first results from a systematic search for high redshift Type Ia supernovae. Using filters in the R-band we discovered seven such SNe, with redshift z = 0…

astro-ph2007

SN 2003du: 480 days in the Life of a Normal Type Ia Supernova

V. Stanishev, A. Goobar, S. Benetti +29

An extensive set of optical and NIR photometry and low-resolution spectra the Type Ia supernova (SN Ia) 2003du was obtained using a number of facilities. The observations started 1…

astro-ph.CO2009

Constraining dust and color variations of high-z SNe using NICMOS on Hubble Space Telescope

S. Nobili, V. Fadeyev, G. Aldering +24

We present data from the Supernova Cosmology Project for five high redshift Type Ia supernovae (SNe Ia) that were obtained using the NICMOS infrared camera on the Hubble Space Tele…

astro-ph.CO2011

The Hubble Space Telescope Cluster Supernova Survey: II. The Type Ia Supernova Rate in High-Redshift Galaxy Clusters

K. Barbary, G. Aldering, R. Amanullah +40

We report a measurement of the Type Ia supernova (SN Ia) rate in galaxy clusters at 0.9 < z < 1.45 from the Hubble Space Telescope (HST) Cluster Supernova Survey. This is the first…

astro-ph.GA2019

Magnification, dust and time-delay constraints from the first resolved strongly lensed Type Ia supernova

S. Dhawan, J. Johansson, A. Goobar +14

We report lensing magnifications, extinction, and time-delay estimates for the first resolved, multiply-imaged Type Ia supernova iPTF16geu, at , using $Hubble\,Space\,Te…