3,299 research outputs found
Properties of Type II Plateau Supernova SNLS-04D2dc: Multicolor Light Curves of Shock Breakout and Plateau
Shock breakout is the brightest radiative phenomenon in a Type II supernova
(SN). Although it was predicted to be bright, the direct observation is
difficult due to the short duration and X-ray/ultraviolet-peaked spectra. First
entire observations of the shock breakouts of Type II Plateau SNe (SNe IIP)
were reported in 2008 by ultraviolet and optical observations by the {\it
GALEX} satellite and supernova legacy survey (SNLS), named SNLS-04D2dc and
SNLS-06D1jd. We present multicolor light curves of a SN IIP, including the
shock breakout and plateau, calculated with a multigroup radiation
hydrodynamical code {\sc STELLA} and an evolutionary progenitor model. The
synthetic multicolor light curves reproduce well the observations of
SNLS-04D2dc. This is the first study to reproduce the ultraviolet light curve
of the shock breakout and the optical light curve of the plateau consistently.
We conclude that SNLS-04D2dc is the explosion with a canonical explosion energy
ergs and that its progenitor is a star with a zero-age
main-sequence mass and a presupernova radius . The
model demonstrates that the peak apparent -band magnitude of the shock
breakout would be mag if a SN being identical to
SNLS-04D2dc occurs at a redshift , which can be reached by 8m-class
telescopes. The result evidences that the shock breakout has a great potential
to detect SNe IIP at z\gsim1.Comment: 5 pages, 5 figures. Accepted for publication in the Astrophysical
Journal Letter
Evaluation of bed shear stress from velocity measurements in gravel-bed river with local non-uniformity
River hydrodynamicsTurbulent open channel flow and transport phenomen
The Unique Type Ib Supernova 2005bf at Nebular Phases: A Possible Birth Event of A Strongly Magnetized Neutron Star
Late phase nebular spectra and photometry of Type Ib Supernova (SN) 2005bf
taken by the Subaru telescope at ~ 270 and ~ 310 days since the explosion are
presented. Emission lines ([OI]6300, 6363, [CaII]7291, 7324, [FeII]7155) show
the blueshift of ~ 1,500 - 2,000 km s-1. The [OI] doublet shows a doubly-peaked
profile. The line luminosities can be interpreted as coming from a blob or jet
containing only ~ 0.1 - 0.4 Msun, in which ~ 0.02 - 0.06 Msun is 56Ni
synthesized at the explosion. To explain the blueshift, the blob should either
be of unipolar moving at the center-of-mass velocity v ~ 2,000 - 5,000 km s-1,
or suffer from self-absorption within the ejecta as seen in SN 1990I. In both
interpretations, the low-mass blob component dominates the optical output both
at the first peak (~ 20 days) and at the late phase (~ 300 days). The low
luminosity at the late phase (the absolute R magnitude M_R ~ -10.2 mag at ~ 270
days) sets the upper limit for the mass of 56Ni < ~ 0.08 Msun, which is in
contradiction to the value necessary to explain the second, main peak
luminosity (M_R ~ -18.3 mag at ~ 40 days). Encountered by this difficulty in
the 56Ni heating model, we suggest an alternative scenario in which the heating
source is a newly born, strongly magnetized neutron star (a magnetar) with the
surface magnetic field Bmag ~ 10^{14-15} gauss and the initial spin period P0 ~
10 ms. Then, SN 2005bf could be a link between normal SNe Ib/c and an X-Ray
Flash associated SN 2006aj, connected in terms of Bmag and/or P0.Comment: 16 pages, 12 figures. Accepted by the Astrophysical Journa
SN 2006aj Associated with XRF 060218 At Late Phases: Nucleosynthesis-Signature of A Neutron Star-Driven Explosion
Optical spectroscopy and photometry of SN 2006aj have been performed with the
Subaru telescope at t > 200 days after GRB060218, the X-ray Flash with which it
was associated. Strong nebular emission-lines with an expansion velocity of v ~
7,300 km/s were detected. The peaked but relatively broad [OI]6300,6363
suggests the existence of ~ 2 Msun of materials in which ~1.3 Msun is oxygen.
The core might be produced by a mildly asymmetric explosion. The spectra are
unique among SNe Ic in (1) the absence of [CaII]7291,7324 emission, and (2) a
strong emission feature at ~ 7400A, which requires ~ 0.05 Msun of
newly-synthesized 58Ni. Such a large amount of stable neutron-rich Ni strongly
indicates the formation of a neutron star. The progenitor and the explosion
energy are constrained to 18 Msun < Mms < 22 Msun and E ~ (1 - 3) 10^{51} erg,
respectively.Comment: Accepted for Publication in the Astrophysical Journal Letters (2007,
ApJ, 658, L5). 8 pages, including 1 table and 3 figures. Typos correcte
Detection of p73 antibodies in patients with various types of cancer: immunological characterization
p53 antibodies have been found in the sera of patients with various types of cancer. The presence of these antibodies is generally associated with p53 accumulation in the tumour that is believed to trigger this humoral response. The recent discovery of 2 new members of the p53 family, p73 and p63, led us to study the specificity of this immune response towards the 3 proteins. Serum samples from 148 patients with various types of cancer were tested for antibodies against p73 and p63 using immunoprecipitation. 72 patients were previously shown to have p53 antibodies whereas 76 were negative. The control group consisted of 50 blood donors. p73 were detected in 22/148 (14.9%) of the cancer patients (11/72 in the group with p53-antibodies and 11/76 in the negative group). Only two sera from the control (4%) were positive. p63 antibodies were detected in only 4/148 (2.7%) of the cancer patients. Epitope mappings were performed and demonstrate that p73 antibodies are directed toward the central region of the p73 protein whereas p53 antibodies react predominantly toward the amino- and the carboxy-terminus of p53. Our results indicate that there is a specific immune response toward the p73 protein in cancer patients, a finding supported by an increasing number of publications describing p73 accumulation in tumoral cells. © 2001 Cancer Research Campaign http://www.bjcancer.co
- …