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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 12 C(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).

An active-target Time Projection Chamber (ELITPC) is being developed at the University of Warsaw to investigate the photo-disintegration reaction 16 O(γ,α) 12 C at energies relevant for nuclear astrophysics (down to ∼ 1 MeV in the centre of mass). Selected results from ongoing R&D activities are presented in this paper.

The designed and constructed at the University of Lodz an electron spectrometer is devoted to "in-beam" measurements. The apparatus is characterized by high efficiency up to 9%, good energy resolution (FWHM = 5 keV at 482 keV) and, what is very important good suppression of delta electrons, positrons, and photons emitted by the targets. This achievement was obtained using a combination of magnetic field in two different layouts: perpendicular and parallel to the axis of the spectrometer being orthogonal to the beamline. The conversion-electron spectrometer coupled to the EAGLE array was successfully tested in an "in-beam" measurement.

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The 134 Nd required for studies of the violation of the K selection rule for electromagnetic transitions in nuclei with mass numbers around 130 can be produced in the reaction of 122 Te with 16 O. The 122 Te target was prepared by the evaporation in a high vacuum. The deposition of the Te isotope on the backing was performed from the very close distance to economize the usage of the isotopic material. The thickness distribution of the target material determined by measurements of the alpha particles energy loss was estimated as 32%. The first test of the target on the 16 O beam with energy of 80 MeV and intensity of 40 enA proved that target prepared by the Te deposition on the Au backing in vacuum is stable in the in-beam conditions and in spite of its relatively high inhomogeneity is suitable for the planned studies.

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