DETAILED ANALYSIS OF NEAR-IR WATER (H2O) EMISSION IN COMET C/2014 Q2 (LOVEJOY) WITH THE GIANO/TNG SPECTROGRAPH

ABSTRACT We observed the Oort cloud comet C/2014 Q2 (Lovejoy) on 2015 January 31 and February 1 and 2 at a heliocentric distance of 1.3 au and geocentric distance of 0.8 au during its approach to the Sun. Comet Lovejoy was observed with GIANO, the near-infrared high-resolution spectrograph mounted a...

Full description

Saved in:
Bibliographic Details
Published in:The Astrophysical journal 2016-10, Vol.830 (2), p.157
Main Authors: Faggi, S., Villanueva, G. L., Mumma, M. J., Brucato, J. R., Tozzi, G. P., Oliva, E., Massi, F., Sanna, N., Tozzi, A.
Format: Article
Language:English
Subjects:
astrobiology
Astrophysics
ASTROPHYSICS, COSMOLOGY AND ASTRONOMY
CARBON NITRIDES
CLOUDS
COMETS
comets: individual (C/2014 Q2 Lovejoy)
COMPARATIVE EVALUATIONS
Confidence limits
DATA ANALYSIS
DISTANCE
Emission analysis
EMISSION SPECTRA
FLUORESCENCE
Fluxes
Infrared analysis
instrumentation: spectrographs
Line spectra
Lunar And Planetary Science And Exploration
methods: data analysis
NEAR INFRARED RADIATION
Nuclear spin
Oort cloud
RESOLUTION
RESONANCE
Spin temperature
TELESCOPES
VIBRATIONAL STATES
WATER
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:ABSTRACT We observed the Oort cloud comet C/2014 Q2 (Lovejoy) on 2015 January 31 and February 1 and 2 at a heliocentric distance of 1.3 au and geocentric distance of 0.8 au during its approach to the Sun. Comet Lovejoy was observed with GIANO, the near-infrared high-resolution spectrograph mounted at the Nasmyth-A focus of the TNG (Telescopio Nazionale Galileo) telescope in La Palma, Canary Islands, Spain. We detected strong emissions of radical CN and water, along with many emission features of unidentified origin, across the 1-2.5 m region. Spectral lines from eight ro-vibrational bands of H2O were detected, six of them for the first time. We quantified the water production rate [Q(H2O), (3.11 0.14) × 1029 s−1] by comparing the calibrated line fluxes with the Goddard full non-resonance cascade fluorescence model for H2O. The production rates of ortho-water [Q(H2O)ORTHO, (2.33 0.11) × 1029 s−1] and para-water [Q(H2O)PARA, (0.87 0.21) × 1029 s−1] provide a measure of the ortho-to-para ratio (2.70 0.76)). The confidence limits are not small enough to provide a critical test of the nuclear spin temperature.
ISSN:0004-637X
1538-4357
DOI:10.3847/0004-637X/830/2/157