117097765
Photometric and Spectroscopic Observations of V1280 Sco
Photometries of B, V, Rc, Ic, y, J, and Ks bands and low dispersion optical spectroscopic observations of Nova V1280 Sco, started soon after the outburst, are reported. We show that V1280 Sco is an Fe II nova and it is going through the historically slowest spectroscopic evolution. The rapid decline observed in the early phase was caused by formation of a dust shell. We estimate the abundances of CNO using the absorption lines on a spectrum at pre-maximum, and find over-abundances by [C/Fe] ~ 1.4, [N/Fe] > 2.0 and [O/Fe] ~ 1.1.
119301785
Five-year optical and near-infrared observations of the extremely slow nova V1280 Scorpii ,
We present optical (B, V, R c , I c and y) and near-infrared (J, H, and K s ) photometric and spectroscopic observations of a classical nova V 1280 Scorpii for five years from 2007 to 2011. Our photometric observations show a declining event in optical bands shortly after the maximum light, which took about 250 days to recover. This event was most probably caused by dust formation. The event was accompanied by a short (∼30 days) re-brightening episode (∼2.5 mag in V), which suggests that there had been some re-ignition of the surface nuclear burning. After 2008, the y band observations show a very long plateau at around y = 10.5 for more than 1000 days until April 2011 (∼1500 days after the maximum light). The nova had taken a very long time (∼50 months) to enter the nebular phase, according to a clear detection of both [O III] 4959 and 5007 and is still continuing to generate the wind caused by H-burning. This finding suggests that historically V1280 Sco is evolving at its slowest ever measured rate. The interval from the maximum light (2007 February 16) to the beginning of the nebular phase is longer than any previously known slow novae: V723 Cas (18 months), RR Pic (10 months), or HR Del (8 months). It suggests that the mass of a white dwarf in the V1280 Sco system might be 0.6 M ⊙ or lower. The distance, based on our measurements of the expansion velocity combined with the directly measured size of the dust shell, is estimated to be 1.1 ± 0.5 kpc.
120962173
Determinant formula and unitarity for the W3 algebra
Abstract The determinant formula for the W 3 algebra is presented. Using the graphical technique it is also shown that the possibly unitary representations are limited.
14833941
Gravitational corrections for supersymmetric gauge theories with flavors via matrix models
Abstract We study the gravitational corrections to the F-term in four-dimensional N = 1 U ( N ) gauge theories with flavors, using the Dijkgraaf–Vafa theory. We derive a compact formula for the annulus contribution in terms of the prime form on the matrix model curve. Remarkably, the full Tr R ∧ R correction can be reproduced as a special momentum sector of a single c = 1 CFT correlator, which closely resembles that in the bosonization of fermions on Riemann surfaces. The N = 2 limit of the torus contribution agrees with the multi-instanton calculations as well as the topological A-model result. The planar contributions, on the other hand, have no counterpart in the topological gauge theories, and we speculate about the origin of these terms.
119226360
NOTE ON ANOMALY CANCELLATION ON SO(32) HETEROTIC 5-BRANE
We show that the gauge, gravitational (tangent-bundle) and their mixed anomalies arising from the localized modes near a 5-brane in the SO(32) heterotic string theory cancel with the anomaly inflow from the bulk with the use of the Green–Schwarz mechanism on the brane, similarly to the E8×E8 5-brane case. We also compare our result with Mourad's analysis performed in the small-instanton limit.