Koehler, A. JACoW Publishing Geneva, Switzerland 2673-5350 978-3-95450-241-7 10.18429/JACoW-IBIC2022-TU3I1 English 348-351 electron laser plasma betatron radiation Contribution to a conference proceedings 2022 2022-12 https://doi.org/10.18429/JACoW-IBIC2022-TU3I1 https://jacow.org/ibic2022/papers/tu3i1.pdf The demonstrations of GeV electron beams and FEL radiation driven by a centimeter-scale device illustrate the tremendous progress of laser-plasma accelerators. In such applications, beam divergence and size, along with beam energy and charge, are critical parameters of electron beams. An insight on the transverse parameters and their dynamics such as beam decoherence can be obtained by diagnostics complemented by betatron radiation detectors. This talk will also provide a brief overview of recent techniques for accessing the transverse phase space.