Extreme Ultraviolet Explorer Right Angle Program Observations of Cool Stars
Extreme Ultraviolet Explorer Right Angle Program Observations of Cool Stars
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极紫外探测器直角计划对冷恒星的观测
DOI：
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发表时间：
1998
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通讯作者：
M. Mathioudakis
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文献类型：
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作者：
D. Christian;J. J. Drake;M. Mathioudakis
极紫外探测器（EUVE）直角程序（RAP）在定点光谱观测期间获得了中心在1000 nm（Lexan/B）、10200 nm（Al/Ti/C）、10400 nm（Ti/Sb/Al）和10550 nm（Sn/SiO）的四个波段的光度数据。RAP观测的灵敏度比EUVE全天巡天观测的灵敏度高20倍。我们提出了24个晚型恒星的RAP观测：BD +03 ° 301，BD +05 ° 300，HR 1262，BD +23 ° 635，BD +22 ° 669，Melotte 25 VA 334，Melotte 25 1366，Melotte 25 59，Melotte 25 65，θ1 Tau，V834 Tau，GJ 2037，BD -21 ° 1074，GJ 205，RE J0532-030、GJ 9287 A、HT Vir、BD +46 ° 1944、Proxima Cen、α Cen A/B、HR 6094、HR 8883、CPD -48 ° 10901和HR 8964。我们从Lexan/B和Al/Ti/C计数率和编目ROSAT位置敏感比例计数器（PSPC）数据获得表面通量。EUVE地表通量与PSPC测量计算的地表通量之间存在合理的相关性。源的时间变异性进行了研究。大多数来源在99%的置信水平下没有显着的变化。在K7 V星星Melotte 25 VA 334、K3 V星星V834 Tau（HD 29697）和K3 + K8 Hyades双星BD +22 ° 669上都探测到了耀斑。在耀斑峰值时，BD +22 ° 669的计数率比静止计数率高6倍，峰值Lexan/B光度为7.9 × 1029 ergs-1。在Lexan/B和Al/Ti/C两个带中都检测到V834 Tau耀斑。Lexan/B和Al/Ti/C的耀斑峰值亮度分别为1.6 × 1029和8 × 1028 ergs-1。
The Extreme Ultraviolet Explorer (EUVE) Right Angle Program (RAP) obtains photometric data in four bands centered at ∼100 Å (Lexan/B), ∼200 Å (Al/Ti/C), ∼400 Å (Ti/Sb/Al), and ∼550 Å (Sn/SiO) during pointed spectroscopic observations. RAP observations are up to 20 times more sensitive than those in the EUVE all-sky survey. We present RAP observations of two dozen late-type stars: BD +03°301, BD +05°300, HR 1262, BD +23°635, BD +22°669, Melotte 25 VA 334, Melotte 25 1366, Melotte 25 59, Melotte 25 65, θ1 Tau, V834 Tau, GJ 2037, BD -21°1074, GJ 205, RE J0532-030, GJ 9287A, HT Vir, BD +46°1944, Proxima Cen, α Cen A/B, HR 6094, HR 8883, CPD -48°10901, and HR 8964. We derive surface fluxes from the Lexan/B and Al/Ti/C count rates and cataloged ROSAT Position Sensitive Proportional Counter (PSPC) data. The EUVE surface fluxes are reasonably correlated with surface fluxes calculated from PSPC measurements. The time variability of the sources has been examined. Most of the sources show no significant variability at the 99% confidence level. Flares were detected from the K7 V star Melotte 25 VA 334, the K3 V star V834 Tau (HD 29697), and the K3 + K8 Hyades binary BD +22°669. The BD +22°669 count rate at the peak of the flare is a factor of 6 higher than the quiescent count rate, with a peak Lexan/B luminosity of 7.9 × 1029 ergs s-1. The V834 Tau flare was detected in both Lexan/B and Al/Ti/C bands. The peak luminosity of the flare is 1.6 × 1029 and 8 × 1028 ergs s-1 for Lexan/B and Al/Ti/C, respectively.