J/ApJ/880/138 Observed transitions of CH_3_OH and CH_3_CHO (Holdship+, 2019) ================================================================================ Observations of CH_3_OH and CH_3_CHO in a sample of protostellar outflow sources. Holdship J., Viti S., Codella C., Rawlings J., Jimenez-Serra I., Ayalew Y., Curtis J., Habib A., Lawrence J., Warsame S., Horn S. =2019ApJ...880..138H ================================================================================ ADC_Keywords: Interstellar medium; Radio lines; Molecular data; Atomic physics Keywords: astrochemistry ; ISM: jets and outflows ; ISM: molecules Abstract: IRAM 30m Observations toward eight protostellar outflow sources were taken in the 96-176GHz range. Transitions of CH_3_OH and CH_3_CHO were detected in seven of them. The integrated emissions of the transitions of each species that fell into the observed frequency range were measured and fit using RADEX and LTE models. Column densities and gas properties inferred from this fitting are presented. The ratio of the A and E-type isomers of CH_3_OH indicates that the methanol observed in these outflows was formed on the grain surface. Both species demonstrate a reduction of terminal velocity in their line profiles in faster outflows, indicating destruction in the post-shock gas phase. This destruction, and a near constant ratio of the CH_3_OH and CH_3_CHO column densities, imply it is most likely that CH_3_CHO also forms on the grain surface. Description: Observations of eight outflow sources were obtained using the IRAM-30m telescope. The observations contain two frequency ranges, the first from 96 to 104GHz and the second from 152 to 176GHz. Observations, taken using the IRAM-30m telescope's EMIR receivers and the Fourier Transform Spectrometer back end, were carried out between 2016 June 2nd and 4th in wobbler switching mode. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table1.dat 76 4 Sources and relevant parameters adapted from Gomez-Ruiz+ (2016MNRAS.462.2203G) table4.dat 202 561 Observed transitions of CH_3_OH and CH_3_CHO -------------------------------------------------------------------------------- See also: J/MNRAS/421/2786 : Modelling of shock waves molecular lines (Flower+ 2012) J/A+A/578/A63 : MHD shock code mhd_vode (Flower+, 2015) Byte-by-byte Description of file: table1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 14 A14 --- Name Name of the central object 16- 17 I2 h RAh Hour of right ascension (J2000) 19- 20 I2 min RAm Minute of right ascension (J2000) 22- 25 F4.1 s RAs Second of right ascension (J2000) 27 A1 --- DE- Sign of declination (J2000) 28- 29 I2 deg DEd Degree of declination (J2000) 31- 32 I2 arcmin DEm Arcminute of declination (J2000) 34- 37 F4.1 arcsec DEs Arcsecond of declination (J2000) 39- 42 F4.1 km/s Vlsr [2.6/6.5] Local Standard of Rest velocity 44- 45 I2 Lsun Lbol [4/25] Bolometric luminosity 47- 49 I3 pc Dist [235/250] Distance 51- 76 A26 arcsec Offsets Blue/Red offsets -------------------------------------------------------------------------------- Byte-by-byte Description of file: table4.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 11 F11.7 GHz Freq [96.27/175.1] Frequency 13- 30 A18 --- QN Resolved quantum number 32- 37 F6.3 [s-1] logAij [-9.9/-3.7] log of transition probability, Aij 39- 45 F7.3 K El [2.3/140.7] Energy level, lower 47- 53 F7.3 K Eu [6.9/148.8] Energy level, upper 55- 56 I2 --- gu [3/42] Upper state degeneracy 58- 63 F6.3 K.km/s I [-0.075/30.41] Integrated emission 65- 69 F5.3 K.km/s e_I [0.006/6.09] Uncertainty in I 71- 75 F5.1 km/s Vmin [-20/12]? Minimum, velocity range 77- 80 F4.1 km/s Vmax [3/40]? Maximum, velocity range 82- 85 F4.1 km/s Vpeak [1/17]? Emission peak velocity 87- 91 F5.3 K Tpeak [0.017/3.4]? Emission peak antenna temperature 93- 97 F5.3 K rms [0.003/0.03] RMS noise in spectrum 99-120 F22.4 cm-2 nu [-1538770577890517/1.36e+16] Upper state column density 122-142 F21.4 cm-2 e_nu [4100957241/8989237408855261] Uncertainty in upper state column density 144-150 F7.4 [-] ln(n/g) [14/35]? Natural log of nu/gu 152-161 F10.4 [-] e_ln(n/g) [-1880/48] Uncertainty in ln(n/g) 163-167 A5 --- Detect Is line detected, True/False? 169-173 A5 --- Blend Are lines blended, True/False? 175-180 F6.3 arcsec Beam [14/25.6] Main beamsize 182-186 F5.3 --- FF [0.38/0.67] Filling factor 188-193 A6 --- Species Species (ch3cho or ch3oh) 195-202 A8 --- Source Source identifier -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Prepared by [AAS], Emmanuelle Perret [CDS] 20-Jan-2021