Search for short time-scale periodicity in the X-ray flux of 4U1700 – 37

Nature ◽  
1979 ◽  
Vol 279 (5713) ◽  
pp. 508-509
Author(s):  
G. BRANDUARDI ◽  
A. K. DUPREE ◽  
P. W. SANFORD ◽  
G. S. G. POLLARD
Keyword(s):  
Time Scale ◽  
Short Time Scale ◽  
X Ray ◽  
Short Time

scholarly journals IPS Observations of Short-Time Scale Interplanetary Activity

1996 ◽  
Vol 154 ◽  
pp. 225-228
Author(s):  
Pradeep Gothoskar ◽  
A. Pramesh Rao
Keyword(s):  
Time Scale ◽  
Solar Maximum ◽  
Component Model ◽  
Scintillation Index ◽  
Short Time Scale ◽  
High Time Resolution ◽  
The Sun ◽  
X Ray ◽  
Average Mass ◽  
Short Time

AbstractWe have carried out a program of continuous Interplanetary Scintillation (IPS) monitoring of the interplanetary activity using Ooty Radio Telescope (ORT). From May 1990 to March 1991, during the 22nd solar maximum, a few radio sources were monitored to provide long stretches of IPS data with a high-time resolution of few minutes. These observations covered 0.3 to 0.8 AU region (12° to 70° elongations) around the sun at several heliographic latitudes. During the observation, we detected 33 short-time scale IPS events which had significant variation in the scintillation index and solar wind velocity. These were considered to be due to travelling interplanetary disturbances.A multi-component model of plasma density enhancement was developed to estimate the geometry and physical properties of these IPS events. Detailed analysis of 20 of these events suggests, 1. fast IPS events were interplanetary signatures of Coronal Mass Ejections (CMEs), 2. the average mass and energy of these events was ~ 1016 gm and 1033 erg respectively, 3. 80% of IPS events were associated with X-ray flares on the sun and 50% were associated with geomagnetic activity at earth. Detailed study of the multi-component model suggests IPS observations at smaller elongations (hence at higher radio frequencies) are more suited to detect fast-moving interplanetary disturbances such as produced by CMEs.

scholarly journals Recent Spectroscopy of X-Ray Sources and Systems Related to Cataclysmic Variables: I

1983 ◽  
Vol 72 ◽  
pp. 21-24
Author(s):  
A.P. Cowley ◽  
D. Crampton ◽  
J.B. Hutchings
Keyword(s):  
Emission Line ◽  
Time Scale ◽  
Cataclysmic Variables ◽  
Short Time Scale ◽  
X Ray ◽  
Spectroscopic Observations ◽  
Low Mass ◽  
Short Time

ABSTRACTWe present results of recent spectroscopic observations of A) some LMC X-ray sources, B) the X-ray burster 1735-44, and C) the peculiar emission-line binary BE UMa. From the short time scale variations and inferred low mass components each shows some similarities to more classical CV's.

scholarly journals Combined long and short time-scale X-ray variability of NGC 4051 withRXTEandXMM-Newton

2004 ◽  
Vol 348 (3) ◽  
pp. 783-801 ◽  
Author(s):  
I. M. McHardy ◽  
I. E. Papadakis ◽  
P. Uttley ◽  
M. J. Page ◽  
K. O. Mason
Keyword(s):  
Time Scale ◽  
Short Time Scale ◽  
X Ray ◽  
Ngc 4051 ◽  
Short Time

An Alternative Test Using Algal Cultures for Testing Chemicals for Toxicity

1993 ◽  
Vol 21 (2) ◽  
pp. 196-201
Author(s):  
Søren Achim Nielsen ◽  
Thomas Hougaard
Keyword(s):  
Size Distribution ◽  
Mitotic Activity ◽  
Time Scale ◽  
Test System ◽  
Short Time Scale ◽  
Toxic Substances ◽  
Alternative Test ◽  
Short Time ◽  
Algal Cultures ◽  
Test Cultures

An alternative test is presented, in which algal cultures are used for testing toxic substances. This test system is based on variations in the size distribution of cells in test cultures as a measurement of growth. Thus, inhibition of mitotic activity is used as a measurement for toxic effects. The test can be performed on a short time-scale and is very sensitive to even weak toxic doses.

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