Results 21 to 30 of about 27,565 (66)
Classification of Supernovae [PDF]
, 2003 The current classification scheme for supernovae is presented. The main observational features of the supernova types are described and the physical implications briefly addressed. Differences between the homogeneous thermonuclear type Ia and similarities among the heterogeneous core collapse type Ib, Ic and II are highlighted.
arxiv +1 more source
The Anatomical Record, EarlyView.Abstract Plutonium was discovered and first synthesized in the early 1940's. Several isotopes of plutonium are used in nuclear technologies, 238Pu for heat generation and 239Pu for energy production and weapons. Both isotopes emit alpha particles, which pose a significant radiation hazard when incorporated into the body.
Scott C. Miller
wiley +1 more source
Possibility of Secondary i- and s-processes Following r-process in the Collapsar Jet
The Astrophysical Journal LettersThe slow and intermediate neutron-capture processes, s - and i -processes, are believed to occur in asymptotic giant branch stars to provide half of the heavy atomic nuclei with A ≥ 90. We suggest a possibility that certain types of outflows found in the
Zhenyu He +7 more
doaj +1 more source
The most massive core collapse supernova progenitors [PDF]
, 2008 The discovery of the extremely luminous supernova SN 2006gy, possibly interpreted as a pair instability supernova, renewed the interest in very massive stars. We explore the evolution of these objects, which end their life as pair instability supernovae or as core collapse supernovae with relatively massive iron cores, up to about $3 M_\odot$.
arxiv +1 more source
Importance of Supernovae at z<0.1 for Probing Dark Energy [PDF]
Phys.Rev. D74 (2006) 103518, 2006 Supernova experiments to characterize dark energy require a well designed low redshift program; we consider this for both ongoing/near term (e.g. Supernova Legacy Survey) and comprehensive future (e.g. SNAP) experiments. The derived criteria are: a supernova sample centered near z=0.05 comprising 150-500 (in the former case) and 300-900 (in the latter ...
arxiv +1 more source
A Slowly Pulsating Run‐Away B Star at High Galactic Latitude Ejected From a Spiral Arm
Astronomische Nachrichten, EarlyView.ABSTRACT We report the discovery of the young B6 V run‐away star LAMOST J083323.18 + 430825.4, 2.5 kpc above the Galactic plane. Its atmospheric parameters and chemical composition are determined from LAMOST spectra, indicating normal composition. Effective temperature (Teff$$ {T}_{\mathrm{eff}} $$ = 14,500$$ \mathrm{14,500} $$ K) and gravity (logg ...
Ulrich Heber +3 more
wiley +1 more source
X-Ray Studies of Supernova Remnants: A Different View of Supernova Explosions [PDF]
, 2010 The unprecedented spatial and spectral resolutions of Chandra have revolutionized our view of the X-ray emission from supernova remnants. The excellent data sets accumulated on young, ejecta dominated objects like Cas A or Tycho present a unique opportunity to study at the same time the chemical and physical structure of the explosion debris and the ...
arxiv +1 more source
A Probabilistic Approach to Classifying Supernovae Using Photometric Information [PDF]
Astrophys.J.659:530-540,2007, 2006 This paper presents a novel method for determining the probability that a supernova candidate belongs to a known supernova type (such as Ia, Ibc, IIL, \emph{etc.}), using its photometric information alone. It is validated with Monte Carlo, and both space- and ground- based data. We examine the application of the method to well-sampled as well as poorly
arxiv +1 more source
Photoinduced Hydrogen Evolution Catalyzed by Co(II) Complexes of N5‐Donor Ligands
Chemistry – A European Journal, EarlyView.Cobalt(II) complexes of three related pentadentate ligands have been investigated as photoelectrochemical catalysts for proton reduction/hydrogen gas evolution in the presence of ruthenium, iridium, or copper‐based photosensitizers. Potential mechanisms for hydrogen evolution have been investigated by time‐resolved transient absorption spectroscopy and
Chuanshuai Li +14 more
wiley +1 more source
NEOWISE-R Caught the Luminous SN 2023ixf in Messier 101
The Astrophysical JournalDuring routine survey imaging, the reactivated Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE-R) serendipitously caught the Type II supernova SN 2023ixf in Messier 101 on the rise, starting day 3.6 through day 10.9, and again on the ...
Schuyler D. Van Dyk +18 more
doaj +1 more source