VizieR Online Data Catalog: Proxima Cen ESPRESSO RV and FWHM (Faria+, 2022)

To add to the 67 observations reported in SM2020, we obtained 52 new ESPRESSO spectra of Proxima, for a total of 117 observations spread over 99 individual nights from 2019-02-10 to 2021-05-06. The measurements were taken in ESPRESSO`s high resolution mode (HR21) with an exposure time of 900s. We used the Fabry Perot (FP) for simultaneous calibration, which allows the instrumental drift to be monitored with a precision better than 10cm/s.

We exclude three observations that were affected by instrumental issues. On the night of 25 April 2019, there was a cooling water temperature increase, which propagated inside the spectrograph. The drift measured on the red detector was 0.007pixel (i.e. 3m/s). This spectrum also shows a signal-to-noise ratio below 1. On the observation of 31 July 2019, the FP exposure was saturated, most likely due to an issue with the neutral density filters. In this situation, the contamination by the FP light on the charge-coupled device may be large, and the drift measurement is likely unreliable. Finally, on the night of 10 April 2021, the reported temperature of the atmospheric dispersion compensator (ADC) was 0K, revealing an issue with the correction. The barycentric Julian days of these three excluded spectra are 2458598.523839, 2458695.52992, and 2459314.583084.

In June 2019, ESPRESSO underwent an intervention to update the fibre link, which improved the instrument's efficiency by up to 50% (Pepe et al., 2021A&A...645A..96P). This intervention introduced an RV offset, leading us to consider separate ESPRESSO18 and ESPRESSO19 datasets. More recently, operations at Paranal were interrupted due to the COVID-19 pandemic and ESPRESSO was taken out of operations between 24 March 2020 and 24 December 2020. This led to a large gap in the observations after the initial campaign. Moreover, a change in one of the calibration lamps after the ramp-up of the instrument is likely to have introduced another RV offset. Therefore, we consider an independent ESPRESSO21 dataset for data obtained after the ramp-up.

In summary, we have 114 available RVs, divided between ESPRESSO18 (50 points), ESPRESSO19 (15 points), and ESPRESSO21 (49 points) subsets.

(1 data file).