Kathryn Daniels - Academia.edu (original) (raw)
Uploads
Papers by Kathryn Daniels
Bookmarks Related papers MentionsView impact
A 96-ks Chandra X-ray observation of rho Ophiuchus cloud core A detected 87 sources, of which 60 ... more A 96-ks Chandra X-ray observation of rho Ophiuchus cloud core A detected 87 sources, of which 60 were identified with counterparts at other wavelengths. The X-ray detections include 12 of 14 known classical T Tauri stars in the field, 15 of 17 known weak-lined TTS, and 4 of 15 brown dwarf candidates. The X-ray detections are characterized by hard, heavily absorbed emission. The mean photon energy of a typical source is 3 keV, and more than half of the detections are variable. Prominent X-ray flares were detected in the unusual close binary system Oph S1, the X-ray bright WTTS DoAr 21, and the brown dwarf candidate GY 31. Time-resolved spectroscopic analysis of the DoAr~21 flare clearly reveals a sequence of secondary flares during the decay phase which may have reheated the plasma. We find that the X-ray luminosity distributions and spectral hardnesses of CTTS and WTTS are similar. We also conclude that the X-ray emission of detected brown-dwarf candidates is less luminous than T Tauri stars, but spectroscopically similar. Simultaneous multifrequency VLA observations detected 31 radio sources at 6 cm, of which ten were also detected by Chandra. We report new radio detections of the optically invisible IR source WLY 2-11 and the faint H-alpha emission line star Elias 24. We confirm circular polarization in Oph S1 and report a new detection of circular polarization in DoAr 21. We find no evidence that X-ray and radio luminosities are correlated in the small sample of TTS detected simultaneously with Chandra and the VLA. We describe a new non-parametric method for estimating X-ray spectral properties from unbinned photon event.
Bookmarks Related papers MentionsView impact
The Journal for Nurse Practitioners, 2007
At least two formulas are commonly used to estimate glomerular filtration rates. This article rev... more At least two formulas are commonly used to estimate glomerular filtration rates. This article reviews these formulas and compares their practical application in clinical practice when the patient is elderly.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
A 96-ks Chandra X-ray observation of rho Ophiuchus cloud core A detected 87 sources, of which 60 ... more A 96-ks Chandra X-ray observation of rho Ophiuchus cloud core A detected 87 sources, of which 60 were identified with counterparts at other wavelengths. The X-ray detections include 12 of 14 known classical T Tauri stars in the field, 15 of 17 known weak-lined TTS, and 4 of 15 brown dwarf candidates. The X-ray detections are characterized by hard, heavily absorbed emission. The mean photon energy of a typical source is 3 keV, and more than half of the detections are variable. Prominent X-ray flares were detected in the unusual close binary system Oph S1, the X-ray bright WTTS DoAr 21, and the brown dwarf candidate GY 31. Time-resolved spectroscopic analysis of the DoAr~21 flare clearly reveals a sequence of secondary flares during the decay phase which may have reheated the plasma. We find that the X-ray luminosity distributions and spectral hardnesses of CTTS and WTTS are similar. We also conclude that the X-ray emission of detected brown-dwarf candidates is less luminous than T Tauri stars, but spectroscopically similar. Simultaneous multifrequency VLA observations detected 31 radio sources at 6 cm, of which ten were also detected by Chandra. We report new radio detections of the optically invisible IR source WLY 2-11 and the faint H-alpha emission line star Elias 24. We confirm circular polarization in Oph S1 and report a new detection of circular polarization in DoAr 21. We find no evidence that X-ray and radio luminosities are correlated in the small sample of TTS detected simultaneously with Chandra and the VLA. We describe a new non-parametric method for estimating X-ray spectral properties from unbinned photon event.
Bookmarks Related papers MentionsView impact
The Journal for Nurse Practitioners, 2007
At least two formulas are commonly used to estimate glomerular filtration rates. This article rev... more At least two formulas are commonly used to estimate glomerular filtration rates. This article reviews these formulas and compares their practical application in clinical practice when the patient is elderly.
Bookmarks Related papers MentionsView impact