A Broadband Spectroscopic Search for CO Line Emission in HDF 850.1: The Brightest Submillimeter Object in the Hubble Deep Field

摘要

We present preliminary results from 70 hours of integration towards the submm-selected extragalactic source HDF 850.1 with the 100 m Green Bank Telescope in an attempt to measure the spectroscopic redshift from mmwavelength emission lines that arise from cool molecular gas fuelling the extremely high rate of star formation activity. In this search for rotational CO emission lines, the tuning frequencies of the GBT spectrometers in the K band ( 18-26 GHz) and the Q band (40-52 GHz) have been guided by the estimated photometrk-redshift (z - 4.1 ± 0.6) for HDF 850.1 derived from rest-frame radio to FIR data. Given the caveat that receiver resonances and baseline ripples have affected these data, no significant molecular lines, including CO(J = 1 - 0) emission, were detected in this deep search.