scholarly journals SMM Coronagraph Observations of Particulate Contamination

1991 ◽  
Vol 112 ◽  
pp. 126-138 ◽  
Author(s):  
O.C. St. Cyr ◽  
T. Warner
Keyword(s):  
Thermal Shock ◽  
White Light ◽  
Space Debris ◽  
Solar Maximum ◽  
Field Of View ◽  
Data Loss ◽  
Solar Maximum Mission ◽  
Particulate Contamination ◽  
Long Duration ◽  
The Times

ABSTRACTSome recent images taken by the white light coronagraph telescope aboard the Solar Maximum Mission (SMM) observatory show bright streaks that are apparently caused by particles associated with the spacecraft. In this report we describe these observations, and we analyze the times of their occurrence. We demonstrate that the sightings occur most often near SMM’s orbital dawn, and we speculate that thermal shock is the mechanism that produces the particles. Although these sightings have not seriously affected the coronagraph’s scientific operations, the unexpected passage of bright material through the field of view of sensitive spaceborne telescopes can lead to data loss or, in some cases, serious detector damage. The topic of space debris has become a significant concern for designers of both manned and unmanned orbiting platforms. The returned samples from the SMM spacecraft and the observations reported here provide a baseline of experience for future orbital platforms that plan long duration missions.

Full field of view super-resolution imaging based on two static gratings and white light illumination

2008 ◽  
Vol 47 (17) ◽  
pp. 3080 ◽  
Author(s):  
Javier García ◽  
Vicente Micó ◽  
Dan Cojoc ◽  
Zeev Zalevsky
Keyword(s):  
White Light ◽  
Super Resolution ◽  
Field Of View ◽  
Light Illumination ◽  
Full Field ◽  
Resolution Imaging ◽  
White Light Illumination

Variations of mesospheric equatorial ozone as observed by the Solar Maximum Mission

1990 ◽  
Vol 17 (3) ◽  
pp. 299-302 ◽  
Author(s):  
Arthur C. Aikin ◽  
William Henze ◽  
David J. Kendig ◽  
Roy Nakatsuka ◽  
Henry J. P. Smith
Keyword(s):  
Solar Maximum ◽  
Solar Maximum Mission

An Ultraviolet Polarimeter For The Solar Maximum Mission

1979 ◽  
Vol 18 (3) ◽  
Author(s):  
John Calvert ◽  
Donald Griner ◽  
Justino Montenegro ◽  
Frank Nola ◽  
Frank Rutledge ◽  
...  
Keyword(s):  
Solar Maximum ◽  
Solar Maximum Mission

Abstract 2645: Longer Ventricular Fibrillation Detection Duration Does Not Increase Rate of Undersensing: Results from the PREPARE Study

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Stephen Moore ◽  
Richard Stern ◽  
Mark L Brown ◽  
Brooke M Heubner ◽  
Jim W Johnson
Keyword(s):  
Primary Prevention ◽  
Ventricular Fibrillation ◽  
Shock Delivery ◽  
Long Duration ◽  
Increase Rate ◽  
The Times ◽  
Over Time

Background: The PREPARE study was designed to evaluate ICD detection and therapy parameters strategically selected to safely reduce all-cause shocks in patients with primary prevention indications by treating only truly sustained fast VT/VF. Electrophysiologic properties have been shown to deteriorate during long-duration VF episodes. There was concern that electrogram deterioration might result in increased undersensing (US) and delayed detection of VF. In this analysis we compared the rate of US between episodes detected with shorter (number of intervals to detect (NID) =12/16) and longer (NID=30/40) detection settings to assess whether delayed detection times for VF increased the rate of US. Methods: All induced VT/VF episodes from PREPARE patients programmed to NID 12/16 or 30/40 and sensitivity 1.2 mV were included in the analysis. US was determined automatically from the stored episode record. The numbers of US and the times from onset through initial detection and from detection to shock were computed. The rates of US over time were compared between the shorter and longer NIDs using a GEE analysis with time as the offset. Results: Seven hundred fifty six VF inductions in 432 patients from the PREPARE study were included in the analysis. There were 319 VF inductions (180 pts) with NID 12/16 and 437 VF inductions (261 pts) with NID 30/40. The average time from VF onset to shock increased from 6.0 to 9.5 seconds with the longer VFNID with no evidence of an increase in the rate of US over time. Conclusion: The longer NID delayed shock delivery by an average of 3.5 seconds but did not result in an increased rate of undersensing.

scholarly journals Preface

1991 ◽  
Vol 336 (1643) ◽  
pp. 323-323
Keyword(s):  
Solar Flare ◽  
Energy Release ◽  
Gamma Rays ◽  
Solar Flares ◽  
Solar Maximum ◽  
Interplanetary Space ◽  
Release Site ◽  
Solar Maximum Mission ◽  
New Information ◽  
Three Space

During the period of the 1980 solar maximum three space missions (P78-1, Solar Maximum Mission and Hinotori ) carried out extensive studies of solar flares. In their different ways all of these missions contributed significant new information to our understanding of the solar flare phenomenon. In this volume the contribution made by these three spacecraft to the study of the energy release and the related creation of high-tem perature plasma, the transport of energy from the primary release site, the production of gamma-rays at energies up to 10 MeV and the ejection of solar matter into interplanetary space are reviewed.

scholarly journals Statistical Study of Solar Eruptive Events Observed with Nobeyama Radioheliograph at 17 GHz

2001 ◽  
Vol 203 ◽  
pp. 401-403
Author(s):  
K. Hori
Keyword(s):  
White Light ◽  
Statistical Study ◽  
Solar Surface ◽  
Solar Maximum ◽  
Small Mass ◽  
Heating Process ◽  
Statistical Features ◽  
Outer Corona

We report statistical features of 49 eruptive prominences observed near solar maximum (1999-2000) with Nobeyama Radiohelograph. Here we focus on the location and related phenomena of the prominence activity. By using white light synoptic maps from LASCO C2 coronagraph, we found that most of the events are associated with some heating process taking place around the prominence site, and occur along pre-existing streamers associated with CMEs as well as small mass ejections. These features suggest that streamers connect the activity on the solar surface toward the outer corona.

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