New High Precision Linelist of H 3 + James N. Hodges, Adam J. Perry, Charles R. Markus, Paul A....
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Transcript of New High Precision Linelist of H 3 + James N. Hodges, Adam J. Perry, Charles R. Markus, Paul A....
New High Precision Linelist of H3+
James N. Hodges, Adam J. Perry, Charles R. Markus, Paul A. Jenkins II, G. Stephen Kocheril, and Benjamin J. McCall
June 16, 2014 - MK06
Outline
• Motivation
• Instrument Description
• Previous Work
• New Lines
• Future Directions
H3+ Fundamental Benchmark
• Simplest polyatomic molecule• Important for ab initio theory• Relativistic, adiabatic and non-
adiabatic effects on PES• Accuracy of order 300 MHz for
low energy• Achieved experimental
precision!O. L. Polyansky, et al. Phil. Trans. R. Soc. A (2012), 370, 5014-5027.C.M. Lindsay and B.J. McCall. J. Mol. Spectrosc. (2001), 210, 66-83.
H3+ Fundamental Benchmark
• QED corrections applied to H3+
• Slightly better accuracy
• Better nonadiabatic corrections are needed
• Requires higher precision data!O.L. Polyanski et al. Phys. Rev. A (2014) 89, 032505.L.G. Diniz et al. Phys Rev. A (2013) 88, 032506.
H3+ Forbidden Rotational Spectrum
• Enable quality prediction of forbidden rotational spectrum
• Predictions are limited to ~600 MHz
• Measuring fundamental, hot, and overtone bands with precision
C.M. Lindsay and B.J. McCall. J. Mol. Spectrosc. (2001), 210, 66-83.
H3+ Astronomical Importance
• Interstellar medium• Deuterium fractionation• Located in gas giants’
ionospheres• Auroral winds • Limited by lab accuracy
T. R. Geballe and T. Oka, Nature (1996), 384, 334.P. Drossart et al. Nature (1989), 340, 539.D. Rego et al. Nature (1999), 399, 121.
Images From: http://solarsystem.nasa.gov/planets/profile.cfm?Object=Jupiterhttp://www.ucl.ac.uk/~ucaptss/work/publications/royalsoc/energy.htm
Spectroscopic TechniqueNoise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy
B. M. Siller, et al. Opt. Express (2011), 19, 24822-7.
VMS
HeterodyneCavity Enhancement
Spectroscopic TechniqueNoise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy
B. M. Siller, et al. Opt. Express (2011), 19, 24822-7.
Ion Selectivity
Sensitivity Large Signal
NICE-OHVMS
Instrumental Layout
OPO
YDFL
EOMLock-In
Amplifier
X & YSignal
Lock-In Amplifier
X & YSignal
40 kHzPlasma
Frequency
80 MHz1 × Cavity Free Spectral Range
90o Phase Shift
I P S
2f
ni = np - ns
AOM
K. N. Crabtree, et al. Chem. Phys. Lett. (2012), 551, 1-6.
Ref. Cell
Freq. Comb
Wave-meter
Comb Calibration
Wave-meter
Freq. CombAOM
[…]
Signal Pump
Comb Calibration
Wave-meter
Freq. CombAOM
[…]
Signal Pump
Comb Calibration
Wave-meter
Freq. CombAOM
[…]
Signal Pump
Comb Calibration
Wave-meter
Freq. CombAOM
[…]
PumpSignal
Production of H3+
• Velocity modulated, l-N2 cooled, positive column
• 40 kHz modulation frequency• 300-500 mTorr of H2
• High J lines - few Torr of He
H3+ Spectra
Doubly Degenerate 2 Band
H3+ Transition Notation
𝐺≡|𝑘− 𝑙|
{𝑃∨𝑄∨𝑅 }( 𝐽 ,𝐺){𝑢∨𝑙 }
Lamb Dips & Saturation• High Power Optical Saturation Lamb dips
• In NICE-OHVMS fm-triplet causes many Lamb dips
Lamb Dips & Saturation• High Power Optical Saturation Lamb dips
• In NICE-OHVMS fm-triplet causes many Lamb dips
Lamb Dips & Saturation• High Power Optical Saturation Lamb dips
• In NICE-OHVMS fm-triplet causes many Lamb dips
Lamb Dips & Saturation• High Power Optical Saturation Lamb dips
• In NICE-OHVMS fm-triplet causes many Lamb dips
Lamb Dips & Saturation• High Power Optical Saturation Lamb dips
• In NICE-OHVMS fm-triplet causes many Lamb dips
Lamb Dips & Saturation• High Power Optical Saturation Lamb dips
• In NICE-OHVMS fm-triplet causes many Lamb dips
Transition Frequencies
R(1,0) transition of ν2 band
Lock-In Amplifier
X & YSignal
Lock-In Amplifier
X & YSignal
Hodges et al. J. Chem. Phys. (2013), 139, 164201.
R(2,2)l transition of ν2 band
Relative Frequency (MHz)
Last Year’s Transition Freq.Transition Freq. (MHz)a Shy (MHz)b
R(1,1)l 80687424.25(62) 80687433.437(250)
R(1,0) 81720377.29(23) 81720371.550(250)
R(1,1)u 81730020.44(38) 81730028.328(250)
R(2,2)l 82804769.99(31) 82804761.121(250)
R(2,1)l 82908940.58(125)
R(2,2)u 84635537.25(54)
R(2,1)u 84724846.57(38)
R(3,3)l 84839013.46(39) 84839021.536(250)
R(3,2)l 84907118.76(134)
R(4,4)l 86774648.52(39)
a. Hodges et al. J. Chem. Phys. (2013), 139, 164201.b. Chen, Peng, Amano, Shy. “Precision Laser Spectroscopy of H3
+”. (2013) 68th ISMS.
Some Additional Transition Freq.Molecule Transition Freq. (MHz)a Us-Prev.
(MHz)HCO+ P(5) 92145080.8(4)
R(3) 92947717.3(5)
ΔEJ=5-3 802636.5(7) -0.6b
CH5+ ??? 86880178.469(126) 0.25c
a. Hodges et al. J. Chem. Phys. (2013), 139, 164201.b. Cazzoli et al. Astrophys. J., Suppl. Ser. (2012), 203, 11.c. S. Schlemmer. Private Communication, (2013).
First Observed Lamb Dip of CH5+
Hodges et al. J. Chem. Phys. (2013), 139, 164201.
HeH+ - Adam J. Perry. FA01, 116 RAL, 8:30 am.
Relative Frequency (MHz)
Transition Freq.Transition Freq. (MHz)a Schlemmer (MHz)b
R(1,1)l 80687424.25(62) 80687422.35(30)
R(1,0) 81720377.29(23) 81720376.57(18)
R(1,1)u 81730020.44(38) 81730019.99(27)
R(2,2)l 82804769.99(31) 82804770.08(51)
R(2,1)l 82908940.58(125)
R(2,2)u 84635537.25(54) 84635537.15(54)
R(2,1)u 84724846.57(38)
R(3,3)l 84839013.46(39)
R(3,2)l 84907118.76(134)
R(4,4)l 86774648.52(39)
a. Hodges et al. J. Chem. Phys. (2013), 139, 164201.b. Asvany, Jusko, Schlemmer. Private Communication, (2014).
New Transition Freq.
Transition Freq. (MHz) St. Dev. (MHz) St. Err. (MHz) Us-Prev. (MHz)
R(4,3)l 86778433.66 0.76 0.38 208.97a
R(3,1)u 87789812.71 1.30 0.53 58.30a
R(3,0) 87844195.67 1.22 0.55 118.86a
R(6,6)l 90368280.18 1.02 0.51 -79.11b
a. T. Oka. Phil Trans R. Soc. London A (1981) 303, 543-549.b. C. M. Lindsay et al. J. Mol. Spectrosc. (2001) 210, 51-59.
𝜎 𝜇=𝜎√𝑛
St. Err. = St. Dev. Of Mean
Future Directions
• Going to continue to measure transitions
• Want to predict forbidden rotational spectrum
• Going to need to expand frequency coverage for our instrument
Acknowledgements
Springborn FellowshipNSF GRF (DGE 11-44245 FLLW)