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Coronae and Chromospheres - Erosita & TIGRE — the Erotig Program — Coronae and chromospheres - eROSITA & TIGRE | The eROTIG program | Jan Robrade Hamburger Sternwarte TIGRE meeting, Li`ege,13 { 15 June 2018 Team: J.H.M.M. Schmitt, C. Schneider, U. Wolter The eROTIG program - What it's about? Besancon model: eROSITA X-ray stars (all, 0.5-2.0 keV) ns00000 (RASS, Guillout+ 1996) 4 ns00090 ns00180 ns05000 ∼ 0.7 million X-ray stars ns05180 3 ns10000 ns10180 > 50 per deg2 (disk), ∼ 6 per deg2 (poles) ns20000 ns20180 2 ns30000 eROSITA: ns30180 ns50000 ◦ ns50180 1 L2 halo-orbit, FOV = 1:03 ns70000 log N (1/deg^2) ns70180 E = 0:3 − 10:0 keV, ∆ E ∼ 80 eV @1 keV ns90000 HEW = 16=26 ", on-axis/FOV @1 keV 0 −14 −2 −1 lim. FX ∼ 1 × 10 erg cm s 1 Stellar surface densities at var. galactic lat./lon. detection limit: 3.0 2.5 2.0 1.5 1.0 0.5 0.0 log S (cts/s) 24 2 LX ≈ 1 × 10 × d (pc) [erg/s] Simulations are based on the Besancon Stellar X-ray population model. Image by J. Robrade. eROSITA all-sky survey (eRASS) { 4 yr survey / 4 h scan rotation X-ray sampling =) ≈ 8 × 5 × 40 [s] largest stellar X-ray sample in human history use TIGRE for near-simultaneous coverage (Ca ii H+K & IRT, Hα...) Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 2 / 15 eROTIG strategy Pt.I Sky focus area eROSITA { German/Russian data share (50/50) eRO DE (Gal. lon 180-360 deg) + La Luz visibility (Dec: −30 ··· + 70 deg) eRO DE fits to Mexican weather good coverage: Nov.-April average coverage: May/June + Sept./Oct. poor coverage: July/August MWL - visibility distribution 'dilutes' observations over the year Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 3 / 15 eROTIG strategy Pt.II Mid-dark - yearly The 9 h strip δ : +40◦; +20◦; 0◦; −20◦ obs: Nov. - May MWL - 1. May MWL - 1. Nov. we think 'ecliptic' (L2 orbit) SRG observes at sun angles 90 ± 20 deg ≈ 2 × 2 h per day for near-simultaneous observations available additional monitoring easy =) 6 months/yr coverage Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 4 / 15 eROTIG target selection Pt. I 'Our proposed eROSITA + TIGRE (eROTIG) program primarily addresses the corona-chromosphere-connection (CCC) in cool stars. The target sample is characterized by the following selection criteria and subgroups:' • X-ray bright stars: RASS detection + counterpart (PSPC > 0:01 cts/s, sep. < 30 ") • Nearby stars: volume-limited samples of magnetically active stars ◦ B − V < 0:45, sp. types early to mid F, 1:3 − 1:6 M { Hot ◦ B − V = 0:45 − 0:58, sp. types late F to early G, 1:1 − 1:3 M { Big suns ◦ B − V = 0:58 − 0:77, sp. types early to late G, 0:9 − 1:1 M { Solar friends ◦ B − V = 0:77 − 1:25, sp. types late G to mid K, 0:7 − 0:9 M { Small suns ◦ B − V > 1:25, sp. types late K to early M, 0:5 − 0:7 M { Red • Joker: Stars of particular interest and/or in eRO RU sky Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 5 / 15 eROTIG target selection Pt. II Aim for about 2 visits (sep. few days) at 2-3 seasons (sep. few months) Large sample required, be realistic... optically bright (V ≤ 9:5 mag), not too red (B − V ≤ 1:5) Simbad database incl. cuts on binarity, luminosity class... ∼ 400 targets, semi-automatic scheduling and analysis test observations started 2017, pre-campaign 2018/02 Hot Big suns Solar friends Small suns Red Joker Size [N] 71 79 140 89 25 ca. 25 D limit [pc] 50/20 50/20 50/30 30/20 30/20 - X-ray frac. 1.0 0.95 0.65 0.75 0.65 ∼ 1.0 T exp [h] 0.19 0.29 0.39 0.5 0.73 typ. 0.4 Table 1: Number of stars, distance cuts (with/without RASS counterpart), RASS detection fraction and average scheduled exposure (per target and visit) for our subsamples. Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 6 / 15 Science cases 3.0 61 Cyg A (K5) - XMM+TIGRE 0.9 XMM-Newton monitoring ] 2.5 1 0.8 s log L =L = −5:5 X bol 2.0 g r e 0.7 [ 0 log R = −4:78 7 1.5 HK 2 0 (Hall+2007: −4:76) 1 1.0 0.6 S-index (MW) X L 0.5 0.5 0.0 Robrade+2012 (updated) 2002 2004 2006 2008 2010 2012 2014 2016 2018 Time [year] ...so far very few objects only corona-chromosphere-connection activity-rotation-age relations 0 dynamic range: log LX=Lbol ≈ −3 ::: − 7, log RHK ≈ −4:2 ::: − 5:2 variability studies & activity cycles very different periods and amplitudes Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 7 / 15 Observational statistics Archive readout: 2018-06-06, Reduction 3.1 eROTIG data program target overlap (Act., RV,...) of 5 { 10% external visit-per-target excess of factor 10 and higher use for cross-checks & testing share to maximize science return Performance scheduling efficiency looks ok (280 targets with 1+ spectra, ∼ 220 h) estimated exposures overall sufficient (S/N aim) lot's of data dropouts (TIGRE / B channel failure) & 100 targets affected (about 35 %) Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 8 / 15 All data: CaII activity S_MWO vs. S8498 0.2 0.1 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 0.5 R'HKx1e5 vs. S8498+S8542 (zoom) 0.4 0.3 0.2 1 2 3 4 5 6 7 8 S8498 vs. S8542 S8498 vs. S8662x5 0.2 S8542 vs. S8662x5 0.1 0.075 0.100 0.125 0.150 0.175 0.200 0.225 0.250 0.275 S-index vs. R'HK vs. IRT Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 9 / 15 Sample data - Red 0.40 HP Cnc, CaII H+K 0.35 0.30 0.9 HP Cnc, CaII IRT 8542 0.25 0.8 0.20 Flux [a.u.] 0.15 0.7 0.10 0.6 0.05 Flux [a.u.] 0.00 3920 3930 3940 3950 3960 3970 3980 0.5 Wavelength (Å) 0.4 8520 8530 8540 8550 8560 Wavelength (Å) HP Cnc (GJ 323 A/B), 'V = 9:41 mag, B − V = 0:98', 50 min. exp. 0 log LX = 28:8 [erg/s], log LX=Lbol = −3:7, (log RHK = −4:4) Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 10 / 15 Sample data - Red 0.45 0.40 AN Sex, CaII H+K 0.35 0.30 0.5 AN Sex, CaII IRT 8542 0.25 0.20 Flux [a.u.] 0.4 0.15 0.10 0.3 0.05 Flux [a.u.] 0.00 3920 3930 3940 3950 3960 3970 3980 0.2 Wavelength (Å) 0.1 8520 8530 8540 8550 8560 Wavelength (Å) AN Sex (GJ 382), V = 9:26 mag, B − V = 1:49, 50 min. exp. 0 log LX = 27:4 [erg/s], log LX=Lbol = −4:8, (log RHK = −4:7) Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 11 / 15 Sample data - Solar friends 0.8 e Vir, CaII H+K 0.7 0.6 0.5 0.36 e Vir, CaII H+K 0.4 Flux [a.u.] 0.3 0.34 0.2 S MWO 0.1 0.32 0.0 3920 3930 3940 3950 3960 3970 3980 Wavelength (Å) 0.30 0 30 60 90 120 150 Time [d] (MJD-58119) e Vir (HD 115383), V = 5:22 mag, B − V = 0:59, Texp = 7:5 min. log LX = 29:6 [erg/s], log LX=Lbol = −4:3 0 log RHK = −4:43 (Wright+2004: −4:40, Hall+2007: −4:47) Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 12 / 15 Sample data - Solar friends 0.8 LW Com, CaII H+K 0.7 0.6 0.5 0.32 LW Com, CaII H+K 0.4 Flux [a.u.] 0.3 0.30 0.2 0.1 S MWO 0.28 0.0 3920 3930 3940 3950 3960 3970 3980 Wavelength (Å) 0.26 0 30 60 90 120 150 Time [d] (MJD-58119) LW Com (HD 111395), V = 6:29 mag, B − V = 0:69, 15 min. exp. log LX = 28:5 [erg/s], log LX=Lbol = −5:0 0 log RHK = −4:58 (Wright+2004: −4:58) Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 13 / 15 Sample data - Solar friends 0.8 61 Vir, CaII H+K 0.7 0.6 0.5 0.18 61 Vir, CaII H+K 0.4 Flux [a.u.] 0.3 0.2 0.16 0.1 S MWO 0.0 3920 3930 3940 3950 3960 3970 3980 Wavelength (Å) 0.14 0 30 60 90 120 150 Time [d] (MJD-58119) 61 Vir (HD 115617), V = 4:74 mag, B − V = 0:70, 5 min. exp. no RASS @ 9 pc, log LX=Lbol < −6:3 0 log RHK = −5:06 (Wright+2004: −5:04, Hall+2007: −4:93) Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 14 / 15 eROTIG future Check data quality and observing success rate Review target sample Implement near-time observation software Launch SRG/eROSITA: March/April 2019 Add more data + diagnostics Add more telescopes (e.g. China, Bulgaria)? Join us... Jan Robrade (Hamburger Sternwarte) eROTIG 14-06-2018 15 / 15.
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