ﻻ يوجد ملخص باللغة العربية
We present results of near-infrared photometric and spectroscopic observations of mid-infrared (MIR) sources that dramatically brightened. Using IRAS, AKARI, and WISE point source catalogs, we found that 4 sources (IRAS 19574+491, V2494 Cyg, IRAS 22343+7501, and V583 Cas) significantly brightened at MIR wavelengths over the 20-30 years of difference in observing times. Little is known about these sources except V2494 Cyg, which is considered a FU Orionis star. Our observation clearly resolves IRAS 22343+7501 into 4 stars (2MASS J22352345+7517076, 2MASS J22352442+7517037, [RD95] C, and 2MASS J22352497+7517113) and first JHKs photometric data for all 4 sources are obtained. Two of these stars (2MASS J22352442+7517037 and 2MASS J22352497+7517113) are known as T Tau stars. Our spectroscopic observation reveals that IRAS 19574+9441 is an M-type evolved star and V583 Cas is a carbon star. 2MASS J22352345+7517076 is probably a YSO, judging from our observation that it has featureless near-infrared (NIR) spectrum and also showed dramatic brightening in NIR (about 4 magnitudes in Ks-band). The possible reasons for dramatic brightening in MIR are discussed in this paper.
We present a systematic study of mid-infrared (mid-IR) emission from 141 nearby supernovae (SNe) observed with the InfraRed Array Camera (IRAC) on Spitzer.These SNe reside in one of the 190 galaxies within 20 Mpc drawn from the ongoing SPIRITS progra
Using the Spitzer Space Telescope, we have obtained rest frame 9-16mu spectra of 11 quasars and 9 radio galaxies from the 3CRR catalog at redshifts 1.0<z<1.4. This complete flux-limited 178MHz-selected sample is unbiased with respect to orientation a
Faint submillimeter sources detected with the Submillimeter Common-User Bolometer Array on the James Clerk Maxwell Telescope have faced an identification problem due to the telescopes broad beam profile. Here we propose a new method to identify such
Using data from the Wide-field Infrared Survey Explorer (WISE) we show that the mid infrared (MIR) colors of low-luminosity AGNs (LLAGNs) are significanlty different from those of post-asymptotic giant branch stars (PAGBs). This is due to a differenc
We investigate the nature of 24micron sources in M33 which have weak or no associated Halpha emission. Both bright evolved stars and embedded star forming regions are visible as compact infrared sources in the 8 and 24micron maps of M33 and contribut