MICROWAVE FREQUENCY TRANSITIONS REQUIRING LASER ABLATED URANIUM METAL

MICROWAVE FREQUENCY TRANSITIONS REQUIRING LASER ABLATED URANIUM METAL DISCOVERED USING CHIRP-PULSE FOURIER TRANSFORM MICROWAVE SPECTROSCOPY B. E. Long and S. A. Cooke Funded by the Department of Energy

Background • 1981: Balle-Flygare Cavity FTMW facilitated the rotational spectroscopic study of transient species Great resolution and sensitivity • 1989: Suenram, Lovas, Matsumura incorporate a laser ablation source “Non-specific production source” * • 2005: Pate and co-workers implement a chirp pulse FTMW spectrometer “The search is over” ** * This meeting: Crabtree, Mc. Carthy RE 03, see also and Zaleski, Stephens, Walker, Legon FD 09 ** Talk FC 03, 60 th ISMS, 2005

Uranium 1. Toxic 2. Dust is pyrophoric 3. Radioactive (a-decay, t 1/2 = 4. 46 x 109 years) 4. Lots of bureaucracy Factor that has been most deleterious to my health

G. S. Grubbs II, R. A. Powoski, D. Jojola and S. A. Cooke. J. Phys. Chem. A 114(2010) 8009. Experiment covers 7 GHz to 18 GHz. Picture credit: C. T. Dewberry.

OCS Laser on Laser off Scale is in MHz

12050 line. 10 shots. None of the observed lines exhibit structure.

U-requiring transitions Frequency / MHz 7999. 8894 8798. 7844 9681. 3895 11181. 0201 11926. 976 11948. 8033 12050. 3949 12173. 5944 S/N in O 2 55/1 11/1 3/1 21/1 74/1 3/1 15/1 11/1 Assignments not available at present. Double resonance experiments inconclusive to date. Autofit software finds multiple 3, and 4 line fits. S/N in Ar 15/1 Not Present 3/1 21/1 Not Present 6/1 3/1

UO 3 is T-shaped

Line Assigner Fit’s Line 2 6 7 8 Freq / MHz 11181. 019 12440. 697 15723. 489 18301. 569 4 4 5 8 2 2 2 4 QN’s 2 4 3 3 3 5 4 8 1 3 3 0 4 5 Obs-Calc. 148243. 000000 -. 039173 -. 056911 Expt’l A = 7764. 89 MHz B = 5013. 92 MHz C = 3054. 41 MHz UO 3 Calc’d A = 7767. 7 MHz B = 5043. 6 MHz C = 3058. 0 MHz Look’s great but lines are predicted that we don’t see.

To do: • Oxygen-17/18 experiments will be attempted in the near future • Stark experiments • E-band measurements Acknowledgements • Department of Energy – “Experimentally characterizing the electronic structures of f-electron systems using advanced high resolution Fourier transform microwave spectroscopies” • Stew Novick, Dan Obenchain, Pete Pringle and all members of the Southern New England Microwave Spectroscopy Consortium.

http: //specfitter. droppages. com/