Time Projection Chamber (TPC) detectors for nuclear astrophysics studies with gamma beams

Gamma-Beams at the HIγS facility in the USA and anticipated at the ELI-NP facility, now constructed in Romania, present unique new opportunities to advance research in nuclear astrophysics; not the least of which is resolving open questions in oxygen formation during stellar helium burning via a precise measurement of the 12C(α,γ) reaction. Time projection chamber (TPC) detectors operating with low pressure gas (as an active target) are ideally suited for such studies. We review the progress of the current research program and plans for the future at the HIγS facility with the optical readout TPC (O-TPC) and the development of an electronic readout TPC for the ELI-NP facility (ELITPC). •Oxygen formation in the 12C + alpha → 16O plus gamma reaction in stellar helium burning determines the C/O ratio at the end of helium burning.•The C/O ratio is one the most important ratio in stellar helium burning; for example, it determines whether a super nova star will collapse to a black hole or a neutron star.•The Study of the photo-dissociation of 16O with gamma-beams allows for improved conditions to measure the time reverse reaction that occurs in stars.•Optical Readout Time Projection Chambers (TPC) detectors have been developed by the University of Connecticut (UConn) and the University of Warsaw (UW) for measurements in nuclear physics. The UConn O-TPC was used at the High Intensity gamma Source (HIgS) facility at Duke University, to study the photo-dissociation of 16O.•The data collected with the O-TPC at the HIgS facility is now being analyzed at the Sheffield Hallam University in the UK.•A new electronic readout TPC has been developed and constructed by the UW-UConn- ELI-NP collaboration, and tested at the IFIN-HH in Bucharest, for a measurement of the dissociation of 16O by neutrons.