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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"

41689 results found.

  1. IPN triangulation of GRB030916 (possible short/hard GRB; large error box)
  2. GRB030913 (=H2849): TAROT Observations
  3. GRB030913: wide field imaging (7 sq.deg) of the error box by MASTER
  4. Magellan Observations of GRB030725 (=H2779)
  5. GRB030913 (=H2849): A GRB Possibly Localized by HETE
  6. GRB 030913: Optical limit at RIKEN
  7. XRF 020427: Gemini-South Spectroscopic Observations of the Host
  8. IBAS detection of bursts from SGR 1806-20
  9. Radio Observations of SGR1806-20
  10. IPN triangulation of GRB030830 (large error box)
  11. GRB 030824: Candidate Follow-Up
  12. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  13. XRF030824: Second-epoch Palomar observations
  14. XRF030824: optical observations
  15. GRB030823: optical observations
  16. XRF030824: Palomar observations
  17. GRB 030824: Candidate Afterglow (or Variable/Flare Star?)
  18. GRB030823: optical observation at Tokyo Tech
  19. RAPTOR observations of GRB030823
  20. Lulin follow-up observations of GRB030823
  21. IPN triangulation of GRB030821 (=H2814; refined error box)
  22. GRB 030821(=H2814): A Faint, Long GRB Localized by the HETE WXM and the IPN
  23. Summary of recent IPN and HETE detections of SGR bursts
  24. Clarification of GCN 2354 on SGR1806-20
  25. IPN detection of continued activity from SGR1806-20
  26. 030813 SGR event (Konus-Wind observation)
  27. SGR 1808-20 (=H2802): A Possible new SGR
  28. GRB 021206 Optical Observations
  29. XRF030723(=H2777): Chandra Fading X-ray Afterglow Confirmed
  30. IPN/HETE summary of recent bursts from SGR1806-20
  31. XRF 030723: Detection of a rebrightening in the optical afterglow
  32. GRB030725: Optical observations
  33. XRF030723, BVRcIc field photometry update
  34. GRB021206 optical counterpart upper limit
  35. XRF030723: Re-analysis of ROTSE-III early images
  36. IPN triangulation of GRB030725 (=H2779; small error box)
  37. XRF030723 (=H2777): Second Epoch Magellan Observations
  38. GRB 030725: optical observations.
  39. GRB030725, optical transient observations
  40. IPN triangulation of GRB030722 (large error box)
  41. XRF030723 Radio Observations
  42. XRF 030723: confirmation of fading optical counterpart
  43. XRF030723(=H2777): Chandra Observations
  44. XRF 030723: VLT spectra
  45. Magellan Observations of XRF030723 (=H2777)
  46. GRB030723: Upper limits from historical observations
  47. GRB030725, possible optical transient
  48. XRF030723: Palomar observations and proposed counterpart
  49. GRB030725 (=H2779): A Bright GRB Localized by HETE
  50. XRF030723: optical observations
  51. XRF030723 (= H2777): Chandra Observations Scheduled
  52. XRF030723, BVRcIc field photometry correction
  53. XRF030723, ROTSE-III Early Observations
  54. XRF030723, BVRcIc field photometry
  55. XRF030723, optical observations
  56. XRF 030723, optical observations
  57. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  58. Konus-Wind detection of the bursts from SGR1806-20 region
  59. SGR 1806-20, submm observations
  60. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  61. IPN triangulation of GRB030717 (annulus)
  62. RXTE PCA Observations of SGR1806-20 Region
  63. GRB030329: Subaru Optical Spectroscopy
  64. Triangulation of GRB030715 (single large error box)
  65. Triangulation of GRB030714 (single large error box)
  66. GRB030329: RTT150 optical observations
  67. GRBlog: Compilation of all GCN Circ. data
  68. GRB030706 triangulation (single large error box)
  69. GRB030329, optical observation in May
  70. IPN triangulation of GRB030626 (single large error box)
  71. GRB030329: second XMM-Newton observation
  72. GRB030418: R optical observations
  73. GRB030329 -- RATAN-600 data in April-May
  74. Final IPN error ellipse for GRB021206 (the polarized GRB)
  75. GRB 021206, Radio afterglow candidate
  76. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  77. GRB030329, SPM optical observations (Correction of GCN2075 R band)
  78. GRB 030528: Infrared Observations and the Proposed IR Counterpart
  79. GRB 030528: Optical Observations
  80. GRB 030528: tentative NIR counterpart
  81. GRB 030528, radio observations
  82. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  83. GRB030329, further radio observations at GMRT
  84. GRB030528, BVRI field photometry
  85. GRB030329, SPM optical observations
  86. GRB030528: Chandra TOO Planned
  87. GRB 030519B: optical observations.
  88. MASTER: optical observation GRB030601
  89. GRB030528(=H2724): Revised SXC Localization
  90. GRB 030329: optical observations
  91. GRB 030329/SN 2003dh: Jitter Episode
  92. GRB 030528, Teramo optical observation
  93. GRB 030528 Bisei optical observation
  94. GRB030528 (H2724): A long GRB localized by HETE
  95. GRB 030329: Correction to GCN 2254
  96. GRB 030329: Optical Observations
  97. GRB 030528: Optical observations at RIKEN
  98. GRB 030416: Optical Observations
  99. GRB 030329: Planned XMM-Newton Observation
  100. GRB030329, Optical observations

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