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Register a new userA WISE view of novae. I. The data
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We present the results of data-mining the Wide-field Infrared Survey Explorer (WISE) archive for data on classical and recurrent novae. We find that the detections are consistent with dust emission, line emission, emission by a stellar photosphere, or a combination of these. Of the 36 novae detected in one or more WISE bands, 16 are detected in all four; thirty-one known novae are not detected by WISE. We also searched for WISE data on post-WISE novae, to gain information about nova progenitors. In this first paper we consider only the WISE data. In future papers we will provide a more detailed modelling of the WISE data, and discuss WISE data on post-WISE novae - including their variability - and will complement the WISE data with data from other IR surveys.
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We present the result of trawling through the WISE archive for data on classical and recurrent novae. The data show a variety of spectral energy distributions, including stellar photospheres, dust and probable line emission. During the mission WISE also detected some novae which erupted subsequent to the survey, providing information about the progenitor systems.
Debris disks around stars are considered as components of planetary systems. Constrain the dust properties of these disks can give crucial information to formation and evolution of planetary systems. As an all-sky survey, textit{InfRared Astronomical Satellite} (iras) gave great contribution to the debris disk searching which discovered the first debris disk host star (Vega). The iras-detected debris disk sample published by Rhee citep{rhe07} contains 146 stars with detailed information of dust properties. While the dust properties of 45 of them still can not be determined due to the limitations with the iras database (have iras detection at 60 $mu$m only). Therefore, using more sensitivity data of textit{Wide-field Infrared Survey Explorer} (wise), we can better characterize the sample stars: For the stars with iras detection at 60 $mu$m only, we refit the excessive flux densities and obtain the dust temperatures and fractional luminosities; While for the remaining stars with multi-bands iras detections, the dust properties are revised which show that the dust temperatures were over estimated in high temperatures band before. Moreover, we identify 17 stars with excesses at the wise 22 $mu$m which have smaller distribution of distance from Earth and higher fractional luminosities than the other stars without mid-infrared excess emission. Among them, 15 stars can be found in previous works.
We report the results of a survey of M31 novae in quiescence. This is the first catalog of extragalactic systems in quiescence to be published, and contains data for 38 spectroscopically confirmed novae from 2006 to 2012. We used Liverpool Telescope (LT) images of each nova during eruption to define an accurate position for each system. These positions were then matched to archival Hubble Space Telescope (HST) images and we performed photometry on any resolved objects that were coincident with the eruption positions. The survey aimed to detect quiescent systems with red giant secondaries, as only these, along with a few systems with bright sub-giant secondaries, will be resolvable in the HST images. There are only a few confirmed examples of such red giant novae in our Galaxy, the majority of which are recurrent novae. However, we find a relatively high percentage of the nova eruptions in M31 may occur in systems containing red giant secondaries. Of the 38 systems in this catalog, 11 have a progenitor candidate whose probability of being a coincidental alignment is less than 5%. We show that, at the 3 sigma limit, up to only two of these eleven systems may be due to chance alignments, leading to an estimate of the M31 nova population with evolved secondaries of up to 24%, compared to the ~3% seen Galactically. Such an elevated proportion of nova systems with evolved secondaries may imply the presence of a much larger population of recurrent novae than previously thought. This would have considerable impact, particularly with regards their potential as Type Ia supernova progenitors.
We use Wide-field Infrared Survey Explorer (WISE) data covering the entire region (~130 deg^2) of the A2199 supercluster at z=0.03 to study the mid-infrared (MIR) properties of supercluster galaxies. We identify a `MIR star-forming sequence in the WISE [3.4]-[12] color-12 mu m luminosity diagram, consisting of late-type, star-forming galaxies. At a fixed star formation rate (SFR), the MIR-detected galaxies at 22 mu m or 12 mu m tend to be more metal rich and to have higher surface brightness than those without MIR detection. Using these MIR-detected galaxies, we construct the IR luminosity function (LF) and investigate its environmental dependence. Both total IR (TIR) and 12 mu m LFs are dominated by late-type, star-forming galaxies. The contribution of active galactic nuclei (AGN)-host galaxies increases with both TIR and 12 mu m luminosities. The contribution of early-type galaxies to the 12 mu m LFs increases with decreasing luminosity. The faint-end slope of the TIR LFs does not change with environment, but the change of faint-end slope in the 12 mu m LFs with the environment is significant: there is a steeper faint-end slope in the cluster core than in the cluster outskirts. This steepening results primarily from the increasing contribution of early-type galaxies toward the cluster. These galaxies are passively evolving, and contain old stellar populations with weak MIR emission from the circumstellar dust around asymptotic giant branch stars.
Eruptions of classical novae are possible sources of lithium formation and gamma-ray emission. Nova remnants can also become Type Ia supernovae (SNe Ia). The contribution of novae to these phenomena depends on nova rates, which are not well established for the Galaxy. Here, we directly measure a Galactic bulge nova rate of $13.8 pm 2.6$ per year. This measurement is much more accurate than any previous measurement of this kind thanks to many years monitoring of the bulge by the Optical Gravitational Lensing Experiment (OGLE) survey. Our sample consists of 39 novae eruptions, $sim$1/3 of which are OGLE-based discoveries. This long-term monitoring allows us to not only measure the nova rate but also to study in detail the light curves of 39 eruptions and more than 80 post-nova candidates. We measured orbital periods for 9 post-novae and 9 novae, and in 14 cases we procured the first estimates. The OGLE survey is very sensitive to the frequently erupting recurrent novae. We did not find any object similar to M31 2008-12a, which erupts once a year. The lack of detection indicates that there is only a small number of them in the Galactic bulge.
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