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11.
VizieR Online Data Catalog: Measured photometry of SN 2014J from HST (Amanullah+, 2014)
R. Amanullah, Tanja Petrushevska, zaključena znanstvena zbirka podatkov ali korpus

Opis: We obtained observations (Program DD-13621; PI: Goobar) of SN 2014J with HST in the four UV broadband filters F218W, F225W, F275W, and F336W for seven epochs using a total of seven HST orbits during Cycle 21. In addition to this we also obtained optical broad-, medium-, and narrowband photometry in filters F467M, F631N, and F845M for visits (1, 3) and optical broadband photometry using F438W, F555W, and F814W for the remaining five visits. All observations were obtained with the Wide-Field Camera-3 (WFC3) using the UVIS aperture UVIS2-C512C-SUB.
Najdeno v: ključnih besedah
Povzetek najdenega: ... Supernovae, Photometry: HST, Photometry: UBVRI, Photometry: infrared, Extinction...
Ključne besede: Supernovae, Photometry: HST, Photometry: UBVRI, Photometry: infrared, Extinction
Objavljeno: 23.01.2018; Ogledov: 2114; Prenosov: 0
.pdf Polno besedilo (430,24 KB)

12.
Probing gas and dust in the tidal tail of NGC 5221 with the type Ia supernova iPTF16abc
Raphael Ferretti, Rahman Amanullah, Ariel Goobar, Tanja Petrushevska, 2017, izvirni znanstveni članek

Opis: Context. Type Ia supernovae (SNe Ia) can be used to address numerous questions in astrophysics and cosmology. Due to their well known spectral and photometric properties, SNe Ia are well suited to study gas and dust along the lines-of-sight to the explosions. For example, narrow Na I D and Ca II H&K absorption lines can be studied easily, because of the well-defined spectral continuum of SNe Ia around these features. Aims. We aim to study the gas and dust along the line-of-sight to iPTF16abc, which occurred in an unusual location, in a tidal arm, 80 kpc from centre of the galaxy NGC 5221. Methods. Using a time-series of high-resolution spectra, we have examined narrow Na I D and Ca II H&K absorption features for variations in time, which would be indicative for circumstellar (CS) matter. Furthermore, we have taken advantage of the well known photometric properties of SNe Ia to determine reddening due to dust along the line-of-sight. Results. From the lack of variations in Na I D and Ca II H&K, we determine that none of the detected absorption features originate from the CS medium of iPTF16abc. While the Na I D and Ca II H&K absorption is found to be optically thick, a negligible amount of reddening points to a small column of interstellar dust. Conclusions. We find that the gas along the line-of-sight to iPTF16abc is typical of what might be found in the interstellar medium (ISM) within a galaxy. It suggests that we are observing gas that has been tidally stripped during an interaction of NGC 5221 with one of its neighbouring galaxies in the past ∼109 yr. In the future, the gas clouds could become the locations of star formation. On a longer time scale, the clouds might diffuse, enriching the circum-galactic medium (CGM) with metals. The gas profile along the line-of-sight should be useful for future studies of the dynamics of the galaxy group containing NGC 5221.
Najdeno v: ključnih besedah
Povzetek najdenega: ...Context. Type Ia supernovae (SNe Ia) can be used to address...
Ključne besede: supernovae: individual: iPTF16abc – galaxies: individual: NGC 5221 – galaxies: ISM – galaxies
Objavljeno: 23.01.2018; Ogledov: 1910; Prenosov: 0
.pdf Polno besedilo (1,57 MB)

13.
Color Me Intrigued: The Discovery of iPTF 16fnm, an SN 2002cx-like Object
A. A. Miller, Tanja Petrushevska, 2017, izvirni znanstveni članek

Opis: 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 discoveries. Here, we describe the Color Me Intrigued experiment, the first from the intermediate Palomar Transient Factory (iPTF) to search for transients simultaneously in the gPTF and RPTF bands. During the course of this experiment, we discovered iPTF 16fnm, a new member of the 02cx-like subclass of Type Ia supernovae (SNe). iPTF 16fnm peaked at Mg 15.09 0.17 mag PTF =-  , making it the second-least-luminous known SN Ia. iPTF 16fnm exhibits all the hallmarks of the 02cx-like class: (i) low luminosity at peak, (ii) low ejecta velocities, and (iii) a non-nebular spectrum several months after peak. Spectroscopically, iPTF 16fnm exhibits a striking resemblance to two other low-luminosity 02cx-like SNe: SN 2007qd and SN 2010ae. iPTF 16fnm and SN 2005hk decline at nearly the same rate, despite a 3 mag difference in brightness at peak. When considering the full subclass of 02cx-like SNe, we do not find evidence for a tight correlation between peak luminosity and decline rate in either the g′ or r′ band. We measure the relative rate of 02cx-like SNe to normal SNe Ia and find rN N 02 Ia cx = 33- + 25 158%. We further examine the g′ − r′ evolution of 02cx-like SNe and find that their unique color evolution can be used to separate them from 91bg-like and normal SNe Ia. This selection function will be especially important in the spectroscopically incomplete Zwicky Transient Facility/Large Synoptic Survey Telescope (LSST) era. Finally, we close by recommending that LSST periodically evaluate, and possibly update, its observing cadence to maximize transient science.
Najdeno v: ključnih besedah
Povzetek najdenega: ...of the 02cx-like subclass of Type Ia supernovae (SNe). iPTF 16fnm peaked at Mg 15.09 0.17...
Ključne besede: methods: observational – surveys – supernovae: general – supernovae: individual (SN 2002cx, SN 2005hk, iPTF 16fnm)
Objavljeno: 23.01.2018; Ogledov: 1928; Prenosov: 0
.pdf Polno besedilo (2,37 MB)

14.
Supernovae seen through gravitational telescopes
Tanja Petrushevska, 2017, doktorska disertacija

Opis: Gravitational lenses such as galaxies and galaxy clusters, can magnify the flux of background galaxies. These galaxies at high redshift can host supernovae (SNe) which, thanks to the magnification boost due to lensing, can be observed, otherwise too faint to be detected by current telescopes. Under the right circumstances, the background galaxies may also have multiple images due to the strong lensing. Of particular interest is to detect lensed supernovae of type Ia (SNe Ia), because of their standard brightness. They could help improve lensing models and, if multiple images are observed, the Hubble constant can be measured independently. In this thesis, we use galaxy clusters as gravitational telescopes to search for lensed SNe at high redshift. We performed ground-based, near-infrared and optical search campaigns towards the massive clusters Abell 1689 and 370, which are among the most powerful gravitational telescopes known. Our search resulted in the discovery of five photometrically classified, core- collapse SNe at redshifts of 0.671 < z < 1.703 with significant magnification from the cluster. Owing to the power of the lensing cluster, we calculated the volumetric core-collapse SN rates for 0.4  z < 2.9, and find good agreement with previous estimates and predictions from cosmic star formation history. During our survey, we also discovered two SNe Ia in A1689 cluster members, which allowed us to determine the cluster Ia rate. Furthermore, we discuss the expectations of finding lensed SNe at high redshift in simulated search campaigns that can be conducted with upcoming ground- and space-based telescopes. Magnification from a galaxy lens also allows for detailed studies of the SN properties at high redshift that otherwise would not be possible. Spec- troscopic observations of lensed high-redshift SNe Ia are of particular interest since they can be used to test for evolution of the standard candle nature of these objects. However, if systematic redshift-dependent properties are found, their utility for future surveys could be challenged. We investigate whether the properties of the strongly lensed and very distant SN Ia PS1- 10afx at z = 1.4, deviates from the well-studied nearby and intermediate populations of normal SNe Ia. In other study, we report the discovery of the first resolved multiply-imaged gravitationally lensed SN Ia.
Najdeno v: ključnih besedah
Ključne besede: supernovae, gravitational telescopes, galaxy clusters, lensed supernovae, strong lensing, astronomical surveys and telescopes
Objavljeno: 23.01.2018; Ogledov: 2507; Prenosov: 0
.pdf Polno besedilo (28,31 MB)

15.
iPTF discovery and identification of bright transients
Thomas Kupfer, Tanja Petrushevska, 2017, drugi članki ali sestavki

Opis: The intermediate Palomar Transient Factory (ATel #4807) reports the discovery of the following bright transients. We report as ATel alerts all objects brighter than 19 mag. Our discoveries are reported in two filters: sdss-g and Mould-I, denoted as g, and I. Both are in the AB magnitude system.
Najdeno v: ključnih besedah
Povzetek najdenega: ... Supernovae, Transient...
Ključne besede: Supernovae, Transient
Objavljeno: 23.01.2018; Ogledov: 1823; Prenosov: 0
.pdf Polno besedilo (338,36 KB)

16.
iPTF discovery and classification of bright transients
Nadejda Blagorodnova, Tanja Petrushevska, 2017, drugi članki ali sestavki

Opis: The intermediate Palomar Transient Factory (ATel #4807) reports the discovery of the following bright transients. We report as ATel alerts all objects brighter than 19 mag. Our discoveries are reported in three filters: sdss-r, Mould-R and Mould-I, denoted as g, r and i. All three are in the AB magnitude system.
Najdeno v: ključnih besedah
Povzetek najdenega: ... Supernovae, Transients...
Ključne besede: Supernovae, Transients
Objavljeno: 23.01.2018; Ogledov: 2111; Prenosov: 0
.pdf Polno besedilo (352,50 KB)

17.
iPTF Discoveries of Recent Type Ia Supernovae Authors:
Semeli Papadogiannakis, Tanja Petrushevska, 2016, drugi članki ali sestavki

Opis: The intermediate Palomar Transient Factory (ATel #4807) reports the discovery and classification of the following Type Ia SNe. Our automated candidate vetting to distinguish a real astrophysical source (1.0) from bogus artefacts (0.0) is powered by three generations of machine learning algorithms: RB2 (Brink et al. 2013MNRAS.435.1047B), RB4 (Rebbapragada et al. 2015AAS...22543402R) and RB5 (Wozniak et al. 2013AAS...22143105W).
Najdeno v: ključnih besedah
Ključne besede: Supernovae, Transient
Objavljeno: 23.01.2018; Ogledov: 1856; Prenosov: 0
.pdf Polno besedilo (344,06 KB)

18.
iPTF Discoveries of Recent Core-Collapse Supernovae
Francesco Taddia, Tanja Petrushevska, 2016, drugi članki ali sestavki

Opis: Abstract The intermediate Palomar Transient Factory (ATel #4807) reports the discovery and classification of the following core-collapse SNe. Our automated candidate vetting to distinguish a real astrophysical source (1.0) from bogus artifacts (0.0) is powered by three generations of machine learning algorithms: RB2 (Brink et al. 2013MNRAS.435.1047B), RB4 (Rebbapragada et al. 2015AAS...22543402R) and RB5 (Wozniak et al. 2013AAS...22143105W).
Najdeno v: ključnih besedah
Ključne besede: Supernovae, Transient
Objavljeno: 23.01.2018; Ogledov: 1795; Prenosov: 0
.pdf Polno besedilo (380,53 KB)

19.
iPTF Discoveries of Recent Type Ia Supernovae
Raphael Ferretti, Tanja Petrushevska, 2016, drugi članki ali sestavki

Opis: The intermediate Palomar Transient Factory (ATel #4807) reports the discovery and classification of the following Type Ia SNe. Our automated candidate vetting to distinguish a real astrophysical source (1.0) from bogus artefacts (0.0) is powered by three generations of machine learning algorithms: RB2 (Brink et al. 2013MNRAS.435.1047B), RB4 (Rebbapragada et al. 2015AAS...22543402R) and RB5 (Wozniak et al. 2013AAS...22143105W).
Najdeno v: ključnih besedah
Ključne besede: Supernovae, Transient
Objavljeno: 23.01.2018; Ogledov: 1834; Prenosov: 0
.pdf Polno besedilo (337,22 KB)

20.
iPTF Discovery of Recent Type Ia Supernovae
Laura Hangard, Tanja Petrushevska, 2016, drugi članki ali sestavki

Opis: The intermediate Palomar Transient Factory (ATel #4807) reports the discovery and classification of the following Type Ia SNe. Our automated candidate vetting to distinguish a real astrophysical source (1.0) from bogus artifacts (0.0) is powered by three generations of machine learning algorithms: RB2 (Brink et al. 2013MNRAS.435.1047B), RB4 (Rebbapragada et al. 2015AAS...22543402R) and RB5 (Wozniak et al. 2013AAS...22143105W).
Najdeno v: ključnih besedah
Ključne besede: Supernovae, Transient
Objavljeno: 23.01.2018; Ogledov: 1814; Prenosov: 0
.pdf Polno besedilo (346,83 KB)

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