From efb37fcbb601979b66bfab6316a5e88e37f17d9c Mon Sep 17 00:00:00 2001 From: jan Date: Thu, 5 Aug 2021 13:17:23 -0700 Subject: [PATCH] first rscvn commit --- config.defaults.yaml | 8 ++++ data/golden/rs_cvn.csv | 91 ++++++++++++++++++++++++++++++++++++++ doc/field_guide.md | 3 ++ doc/field_guide__rs_cvn.md | 49 ++++++++++++++++++++ 4 files changed, 151 insertions(+) create mode 100644 data/golden/rs_cvn.csv create mode 100644 doc/field_guide__rs_cvn.md diff --git a/config.defaults.yaml b/config.defaults.yaml index 137a47d9..78e0f993 100644 --- a/config.defaults.yaml +++ b/config.defaults.yaml @@ -112,3 +112,11 @@ docs: variable: coordinates: [102.5537728, 44.1032507] title: Variable stars + rs_cvn_1: + coordinates: [344.8924,6.1829] + period: 2.834970 + title: RS CVn + rs_cvn_2: + coordinates: [349.1745,36.5569] + period: 5.900631 + title: RS CVn with modulation diff --git a/data/golden/rs_cvn.csv b/data/golden/rs_cvn.csv new file mode 100644 index 00000000..f9d121e6 --- /dev/null +++ b/data/golden/rs_cvn.csv @@ -0,0 +1,91 @@ +ra,dec +116.5460,29.4144 +106.1385,36.1189 +202.5821,29.0948 +118.4703,21.1640 +212.1741,-8.4681 +260.7941,22.0534 +321.8671,7.7000 +13.5716,2.4428 +107.7544,54.8618 +127.7441,6.7789 +115.1254,24.9292 +112.0675,30.5794 +14.9901,30.8278 +29.1911,32.6006 +108.8383,28.2651 +220.4281,15.0601 +110.7043,34.5766 +32.9781,-12.9502 +118.8534,12.5069 +100.1043,57.4237 +35.0531,14.6167 +17.8315,-9.4326 +113.3872,34.2356 +45.6811,20.2800 +257.2931,54.4960 +5.4266,38.2104 +114.6323,35.7114 +113.9801,32.2946 +123.2301,2.9129 +110.4553,30.0514 +255.2221,36.9997 +247.8471,-2.2064 +224.7341,-10.9800 +242.5281,6.9274 +261.3541,40.0359 +128.1971,10.8852 +53.0791,-3.5412 +239.8731,25.3449 +201.5471,-5.4531 +102.7434,34.3382 +39.0661,38.3869 +21.5161,-12.1272 +38.9121,39.0369 +244.7741,0.0124 +110.6667,33.1876 +131.3171,2.4905 +108.1823,41.2532 +240.2661,14.9707 +113.6721,49.7235 +331.4371,21.8907 +101.7798,44.6628 +247.0821,37.3663 +101.6630,61.3512 +216.4391,-0.4998 +110.1130,40.7817 +118.1008,36.6713 +116.3274,31.2897 +15.6330,16.0505 +218.8711,-17.8939 +110.2710,41.7037 +41.3581,10.2480 +0.2640,10.9568 +118.4295,12.3404 +118.8351,14.8517 +109.4087,35.9424 +108.9465,53.8810 +18.4741,37.9520 +108.3139,45.5459 +17.2413,-13.3874 +105.3045,52.5338 +131.3311,20.0841 +51.9181,20.1754 +16.7225,35.5003 +102.5070,43.5569 +11.9440,20.4947 +10.0162,30.0036 +37.2301,4.5752 +56.1241,29.9870 +18.0916,29.8321 +41.6891,0.1590 +141.6521,25.6570 +113.7695,20.5859 +15.7480,32.8324 +264.6621,36.0267 +48.1291,-3.1162 +115.2033,44.1012 +115.2155,26.7927 +42.5701,17.1515 +113.1125,43.0799 +230.0761,-12.1313 diff --git a/doc/field_guide.md b/doc/field_guide.md index 4a5bb771..26cdecdf 100644 --- a/doc/field_guide.md +++ b/doc/field_guide.md @@ -35,3 +35,6 @@ for more details on the taxonomy. ```{include} ./field_guide__lpv.md ``` + +```{include} ./field_guide__rs_cvn.md +``` diff --git a/doc/field_guide__rs_cvn.md b/doc/field_guide__rs_cvn.md new file mode 100644 index 00000000..ad1a7f7d --- /dev/null +++ b/doc/field_guide__rs_cvn.md @@ -0,0 +1,49 @@ +## RS CVn (rscvn) + + +### Classification and numbers +- Supertypes + - variable + - periodic + - binary +- Occurrence rate: common, about 105 expected in ZTF data + + +### ZTF light curves +![ZTF rscvn](data/rs_cvn_1.png) +![ZTF rscvn flaring](data/rs_cvn_2.png) + +#### Description +RS Canum Venaticorum stars are binary systems in which one or both stars are chromospherically active. The surface of the star (typically F or G main-sequence or subgiant) is covered with groups of spots, which makes the surface brightness inhomogenious. These spots rotate with a period close to the orbital period. However, the spot rotation period can differ slightly from the orbital period, which causes the lightcurve shape to change over timescales of years. The variability of the wave's amplitude is explained by the existence of a long-period stellar activity cycle similar to the 11-year solar activity cycle, during which the number and total area of spots on the star's surface vary. Small amplitude flares, another signature of chromospheric activity, can also be observed in some cases. + +Other types of variable stars with chromospheric activaty (which we do not consider of the RS CVn type): +- white dwarf or hot subdwarf stars with a chromospherically active companion +- BY Dra variables (single rotating star, typically K or M type) +- UV Cet variables (flaring low mass main sequence stars) +- single solar-type stars with active chromospheres +- T Tau variables (young chromospherically active stars) +- W UMa binaries (overcontact binaries) +- FK Com stars (rapidly rotating single stars) +- single giants with active chromospheres + +#### Light curve characteristics +- periodic variable +- period range: 0.5-50 days +- amplitude: 0.01 up to 0.6 mag +- light curve shape: + - sinusoidal; or with two maximima and minima of different heights and depths + - the shape can change over timescales of years (modulation) + - they can show eclipses, but this is not required + - can show stellar flares + + +#### Other characteristics and selection methods +- the chromospherically active star is a F or G main-sequence star +- often show Ca-II emission lines + +![HR diagram of RS CVn](data/hr__rs_cvn.png) +![RA/Dec diagram of RS CVn](data/radec__rs_cvn.png) + +### References and further reading: +- VSX: https://www.aavso.org/vsx/index.php?view=about.vartypes +- Sterken & Jasschek: Light curves of variable stars