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We describe Spitzer/MIPS observations of the double cluster, h and $chi$ Persei, covering a $sim$ 0.6 square-degree area surrounding the cores of both clusters. The data are combined with IRAC and 2MASS data to investigate $sim$ 616 sources from 1.25-24 $mu m$. We use the long-baseline $K_{s}$-[24] color to identify two populations with IR excess indicative of circumstellar material: Be stars with 24 $mu m$ excess from optically-thin free free emission and 17 fainter sources (J$sim$ 14-15) with [24] excess consistent with a circumstellar disk. The frequency of IR excess for the fainter sources increases from 4.5 $mu m$ through 24 $mu m$. The IR excess is likely due to debris from the planet formation process. The wavelength-dependent behavior is consistent with an inside-out clearing of circumstellar disks. A comparison of the 24 $mu m$ excess population in h and $chi$ Per sources with results for other clusters shows that 24 $mu m$ emission from debris disks rises from 5 to 10 Myr, peaks at $sim$ 10-15 Myr, and then falls from $sim$ 15/20 Myr to 1 Gyr.
We analyze 8 sources with strong mid-infrared excesses in the 13 Myr-old double cluster h and chi Persei. New optical spectra and broadband SEDs (0.36-8 mu_m) are consistent with cluster membership. We show that material with T ~ 300-400 K and Ld/Lst
In order to study the stellar population and possible substructures in the outskirts of Double Cluster $h$ and $chi$ Persei, we investigate using the GAIA DR2 data a sky area of about 7.5 degrees in radius around the Double Cluster cores. We identify
We present blue optical spectra of 92 members of h and chi Per obtained with the WIYN telescope at Kitt Peak National Observatory. From these spectra, several stellar parameters were measured for the B-type stars, including V sin i, T_eff, log g_pola
The Gamma Ray Burst (GRB) 180720B is one of the brightest events detected by the Fermi satellite and the first GRB detected by the H.E.S.S. telescope above 100 GeV. We analyse the Fermi (GBM and LAT) and Swift (XRT and BAT) data and describe the evol
Spitzers final Infrared Array Camera (IRAC) observations of SN 1987A show the 3.6 and 4.5 $mu$m emission from the equatorial ring (ER) continues a period of steady decline. Deconvolution of the images reveals that the emission is dominated by the rin