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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

28066 results found.

  1. GRB010126: CONCAM crude optical limits during GRB
  2. GRB010126 optical observations
  3. Optical Observations of GRB 001018 at Keck
  4. Optical observations of GRB 001018 with JCAM
  5. GRB 001212 Optical Observation
  6. GRB 001212 Optical Observation
  7. Confirmation of IPN position for GRB001204
  8. GRB001120: Gunn-i observations
  9. WSRT 4.8 GHz observations of GRB001109
  10. Optical/NIR observations of GRB001109
  11. GRB 001109: deep JHK upper limits
  12. GRB 001109 X-ray afterglow with BeppoSAX
  13. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  14. GRB001007: Optical observations
  15. GRB001007, Radio observations
  16. GRB 001018, Possible Radio Afterglow
  17. GRB 000926: Improved Absorber Redshift
  18. The Likely Optical/Infrared Afterglow of GRB 001011
  19. HETE positions added to GCN
  20. GRB000926 - Amateur Optical Observations
  21. GRB001007: Optical observations
  22. CONCAM null result on GRB001005
  23. GRB 000926 Chandra Observation
  24. Public availability of BeppoSAX data of GRB000926
  25. GRB000926: X-ray afterglow by BeppoSAX: revised fluxes (fwd)
  26. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  27. GRB000926 : increasing optical decay slope
  28. GRB 000926: Lightcurve Update and Predictions
  29. GRB 000926, optical observation by Oksanen (vsnet-grb)
  30. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  31. CONCAM crude optical limits before and after GRB000926
  32. GRB 000926: Preliminary R-band Lightcurve
  33. GRB 000926 HST/Chandra TOO Status
  34. Spectroscopic Redshift of GRB 000926
  35. GRB000911: Optical observations
  36. GRB000830, BVRI field photometry
  37. GRB000830: Optical observations
  38. "Snapshot" afterglow IDs and GRB 000830
  39. GRB000830: Optical observations
  40. HST/STIS observations of the chaotic environment of GRB 980613
  41. GRB000812, Radio observations
  42. GRB 991208 Host Galaxy Imaging
  43. GRB 990510: Possible detection of a host galaxy
  44. GRB 991216, HST/STIS observations
  45. GRB000620, Radio Observations
  46. GRB981226, HST/STIS observations of the host galaxy
  47. GRB000630, optical observations
  48. GRB 000630: Detection of the Optical Afterglow
  49. GRB000630, BVRI Field Photometry
  50. GRB 990506, HST/STIS Observations of the Host Galaxy
  51. GRB990308, HST/STIS observations of the host galaxy
  52. GRB000620: BeppoSAX WFC and GRBM detection
  53. GRB990123, HST/STIS observations of the host galaxy
  54. GRB000615, further R-band photometry
  55. GRB000615, R-band photometry
  56. GRB980425, HST/STIS observations of the host galaxy
  57. GRB000528: follow-up X-ray measurements and update of IPN annulus
  58. Optical Follow-up of GRB000529 Error Box
  59. GRB000604 optical non-detection
  60. GRB000604, optical observations
  61. GRB 000418: Detection of the Host Galaxy
  62. X-ray Afterglow of GRB 000529
  63. GRB000519, BVRI field photometry
  64. GRB 000418, Optical observation
  65. GRB000508B, BVR field photometry
  66. Possible GRB-related phenomenon
  67. GRB000424, UBVRI field photometry
  68. GRB000424, optical observations
  69. GRB 000429, UBVRI field photometry
  70. GRB000418, Radio detection
  71. GRB000418, K'-band photometry
  72. GRB 000418, Optical Observation
  73. GRB 000418, optical observation
  74. GRB 000418, Optical Observation
  75. GRB000424, optical observations
  76. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  77. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  78. Budget cuts in BeppoSAX operations: impact on GRB observations
  79. GRB000408: Optical CCD Observations from MIRO
  80. GRB000326 Optical Observations
  81. GRB 000313 - optical transient in the BATSE error box
  82. GRB 000301C: A Precise Redshift Determination
  83. GRB 000301C: HST/STIS CCD Imaging of the field
  84. GRB 000301C: K' Observations
  85. GRB000301C - Host galaxy not detected in R (?)
  86. GRB 000301c near-IR observations
  87. GRB 000301C, Optical Color
  88. GRB000301C 250 GHz detection
  89. GRB000301C, near-infrared observations (JHK' photometry)
  90. GRB000301C, optical observations
  91. GRB000301c, near-infrared observations
  92. GRB 000214 near-IR observations
  93. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  94. GRB000210, Radio Observations
  95. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
  96. GRB000214: BeppoSAX GRBM and WFC Detection
  97. GRB000210 X-ray afterglow
  98. GRB000214: X-ray afterglow candidate
  99. Correction to Chandra Position of GRB000210 afterglow
  100. Optical observations of the Chandra X-ray source for GRB000210

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