BEGIN:VCALENDAR VERSION:2.0 PRODID:Data::ICal 0.22 BEGIN:VEVENT DESCRIPTION:Aaron Calvin\, Georgia Tech\n\n
C
aH+ is an astrophysically relevant molecule with proposed appli
cations in fundamental physics. We use CaH+ co-trapped with Dop
pler cooled Ca+ to perform spectroscopy using two-photon photod
issociation with a frequency doubled\, mode locked Ti:sapph laser. This me
thod was used to measure the vibronic spectrum of the 11 &Sigma
\;\, v = 0  \;21 &Sigma\;\, v'\; = 0\, 1\, 2\, 3 transit
ions. Spectroscopy on the deuterated isotopologue\, CaD+ confir
med a revised assignment of the CaH+ vibronic levels and a disa
greement with MS-CASPT2 theoretical calculations by approximately 700 cm-1. Updated high-level coupled-cluster calculations that include
core-valence correlations reduce the disagreement between theory and exper
iment to 300 cm-1. \; The broad bandwidth of the pulsed Ti:
sapph provided an advantage for the initial search for transitions\, but d
id not allow spectral resolution of rotational transitions. Pulse shaping
was applied to spectrally narrow the linewidth of the pulsed laser to obta
in rotational constants for the 21 &Sigma\;\, v'\; = 0\, 1\,
2\, 3 and 11 &Sigma\;\, v = 0 states. This measurement has val
ue in the control of quantum states of the molecule for high precision mea
surements of rovibrational transitions using quantum logic. Molecule-cold
atom collisions for possible buffer gas cooling can also be tested using t
his method.