Alexander V. Lapinov, G.Yu.Golubiatnikov, S.P.Belov Inst. of Applied Physics of the Russian Academy of Sciences, Nizhny Novgorod, Russia CH 3 OH sub-Doppler Spectroscopy MF04 Ohio

List of 155+9? molecules discovered in interstellar medium ( Molecules with Two Atoms CH CN CH + OH CO H 2 SiO CS SO SiS NS C 2 NO HCl NaCl AlCl KCl AlF PN SiC CP NH SiN SO + CO + HF LiH? SH FeO? N 2 CF + O 2 PO AlO Molecules with Three Atoms H 2 O HCO + HCN OCS H 2 S HNC N 2 H + C 2 H SO 2 HCO HNO HCS + HOC + c-SiC 2 MgNC C 2 S C 3 CO 2 CH 2 C 2 O NH 2 NaCN N 2 O MgCN H 3 + SiCN AlNC SiNC HCP CCP AlOH Molecules with Four Atoms NH 3 H 2 CO HNCO H 2 CS C 3 N HNCS HOCO + l-C 3 H C 3 O HCNH + H 3 O + C 3 S c-C 3 H C 2 H 2 HCCN H 2 CN c-SiC 3 CH 3 C 3 N - PH 3 ? HCNO C 4 ? HOCN? HSCN Molecules with Five Atoms HC 3 N HCOOH CH 2 NH NH 2 CN H 2 CCO C 4 H SiH 4 c-C 3 H 2 CH 2 CN C 5 SiC 4 l-C 3 H 2 CH 4 HC 2 NC HNC 3 H 2 COH + C 4 H - CNCHO Molecules with Six Atoms CH 3 OH CH 3 CN HCONH 2 CH 3 SH C 2 H 4 C 5 H CH 3 NC? HC 2 CHO l-H 2 C 4 HC 3 NH + C 5 N HC 4 H HC 4 N c-H 2 C 3 O CH 2 CNH C 5 N - Molecules with Seven Atoms HCOCH 3 CH 3 C 2 H CH 3 NH 2 CH 2 CHCN HC 5 N C 6 H c-C 2 H 4 O CH 2 CHOH C 6 H - Molecules with Eight Atoms HCOOCH 3 CH 3 C 3 N C 7 H CH 3 COOH CH 2 OHCHO HC 6 H H 2 C 6 CH 2 CHCHO CH 2 CCHCN NH 2 CH 2 CN Molecules with Nine Atoms CH 3 CH 2 OH CH 3 CH 2 CN CH 3 OCH 3 HC 7 N CH 3 C 4 H C 8 H CH 3 CONH 2 C 8 H - CH 2 CHCH 3 Molecules with Ten Atoms (CH 3 ) 2 CO HOCH 2 CH 2 OH NH 2 CH 2 COOH? CH 3 CH 2 CHO CH 3 C 5 N Molecules with Eleven Atoms HC 9 N CH 3 C 6 H C 2 H 5 OCHO Molecules with Twelve Atoms C 6 H 6 CH 3 OC 2 H 5 ? (CH 2 OH) 2 CO? C 3 H 7 CN Molecules with Thirteen Atoms : HC 11 N

Location Pico Veleta, Sierra Nevada, 45km from Granada, Spain, Long: 3°23’33.7”(W), Lat: 37°03’58.3”(N), Alt: 2920m Date V LSR (km/s) FWHM(m/s) 20-Aug (92) 186.2(10) 14-Sep (101) 186.1(17) (137)=0.5(10)kHz ΔV Tk=10K =124м/с, ΔV NT =139м/с Study of gas motions in star-forming regions (2003 ApJ 592, L95; 2006 SPIE ) Precision of radio astronomical measurements

Sketch of Lamb-dip spectrometer BWO Second harmonics detector Lamb W.E rd Int.Conf.Quant.Electr., Paris Lamb W.E.1964 Phys.Rev.134,1429 MacFarlane R.A., Bennett W.R., & Lamb W.E Appl. Phys. Lett. 2, 189 Dryagin Yu.A Radiophys. & Quant. Electr. 13, 107 Line center uncertainty (Landman et al ApJ 261, 732): P~1mTorr

G.Yu.Golubiatnikov, A.V.Lapinov, A.Guarnieri, R. Knöchel, 2005 J.Molec.Spectrosc. 234, 190 Precise Lamb-dip measurements of millimeter and submillimeter wave rotational transitions of 16 O 12 C 34 S All frequencies <500 GHz were measured at  1 kHz accuracy, at 0.89 – 1.1 THz – with RAD accuracy: ~10 кГц Main result: precise frequency comb with 12 GHz period, good for lab frequency calibration with extremely small pressure shift (< 6 kHz/Torr in OCS J=3–2, De Vreede et al. 1988) Precise sub-Doppler spectroscopy of OCS ТОР25 – SciDir2005

Accuracy of OCS sub-Doppler spectroscopy

Torsion-rotation spectroscopy of CH 3 OH Paul Jansen et al Phys.Rev.A 84, Sensitivity of transitions... to m e /m p Li-Hong Xu et al J.Mol.Spectr. 251, 305 Torsion-rotation global analysis...

Examples of CH 3 OH-E v t =0 measurements

Sketch of energy level splitting in CH 3 OH-E v t =0

Sketch of energy level diagram for CH 3 OH v t =1

Examples of CH 3 OH-A v t =1 measurements I H =1? I H =2?

Examples of CH 3 OD-A v t =0 measurements I=5/2? I=1/2?

Sub-Doppler spectrometer at the Institute of Applied Physics, N.Novgorod