J. Kastner and M. Richmond, Rochester Institute of Technology; T. Simon, Institute for Astronomy, Honolulu; N. Grosso, Laboratoire d'Astrophysique de Grenoble; D. Weintraub, Vanderbilt University; and K. Hamaguchi, Universities Space Research Association, Greenbelt, report that they obtained a 9630-s Director's Discretionary Time exposure on Nov. 18 with the Chandra X-ray Observatory's Advanced CCD Imaging Spectrometer imaging array (ACIS-I) of a field centered at R.A. = 4h41m35s.8, Decl. = +54d19'20" (equinox 2000.0), the position of a low-luminosity, eruptive, young stellar object reported by Stecklum (CBET 690). No x-ray source is detected within several arcminutes of this position. The upper limit on the (0.5- to 8.0-keV) Chandra/ACIS-I count rate within a 10"-radius circular aperture centered on the Stecklum position is < 0.67 count/ks (99-percent confidence; Kraft et al. 1991, Ap.J. 374, 344); this corresponds to an upper limit on observed x-ray fluxes of < 3.9 x 10**(-15) and < 5.0 x 10**(-15) erg cm**(-2) s**(-1) for assumed plasma temperatures of 10 and 30 MK, respectively. The emergent source x-ray luminosity is hence constrained to be less than about 2 x 10**(28) erg s**(-1), assuming that the distance to the L1415 cloud is 170 pc. The intrinsic source x-ray luminosity is not well constrained, however, given that the star is likely encircled by a circumstellar disk that is viewed almost edge-on (Stecklum et al. 2006, http://xxx.lanl.gov/abs/astro-ph/?0611314).
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Central Bureau Electronic Telegrams, 760, 1 (2006). Edited by Green, D. W. E.
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