2 HOPS ivo://irsa.ipac/Herschel/Spectra/HOPS NASA/IPAC Infrared Science Archive HOPS team 2016-10-01 IRSA Support Team irsasupport@ipac.caltech.edu The Herschel Orion Protostar Survey (HOPS, KPOT_tmegeath_2) is a sample of 410 young stellar objects (YSOs) in the Orion molecular clouds, selected from Spitzer data. Most objects have near-infrared photometry from 2MASS, mid- and far-infrared data from Spitzer and Herschel, and submillimeter photometry from APEX; thus, the SEDs cover 1.2 - 870 microns and are used to classify the sample into protostellar classes. Of the 410 YSOs, 330 have Spitzer and Herschel data and are mostly protostars; the remaining objects include likely extragalactic contaminants and faint YSOs. Using mid-IR spectral indices and bolometric temperatures, the sample of 330 YSOs is classified into 92 Class 0 protostars, 125 Class I protostars, 102 flat-spectrum sources, and 11 Class II pre-main-sequence stars. HOPS also implements a simple protostellar model (including a disk in an infalling envelope with outflow cavities) to generate a grid of 30,400 model SEDs and uses it to determine the best-fit model parameters for each protostar. https://irsa.ipac.caltech.edu/data/Herschel/HOPS/overview.html Archive Research 1 https://irsa.ipac.caltech.edu/SSA?COLLECTION=herschel_hops& minimal survey archival ICRS 83.85233 -5.92595 0.5 Infrared Millimeter