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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').
Advanced Search

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.

Advanced Search Examples (click to copy):

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

15985 results found.

  1. GRB030723: Upper limits from historical observations
  2. GRB030725, possible optical transient
  3. XRF030723: Palomar observations and proposed counterpart
  4. GRB030725 (=H2779): A Bright GRB Localized by HETE
  5. XRF030723: optical observations
  6. XRF030723 (= H2777): Chandra Observations Scheduled
  7. XRF030723, BVRcIc field photometry
  8. XRF 030723, optical observations
  9. XRF030723, optical observations
  10. XRF 030723, optical observations
  11. XRF030723 (=H2777): An X-ray Flash Localized by the HETE WXM and
  12. GRB030723, optical observations
  13. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  14. GRB030329: Subaru Optical Spectroscopy
  15. GRB030329: RTT150 optical observations
  16. GRBlog: Compilation of all GCN Circ. data
  17. GRB030329, optical observation in May
  18. GRB030418: R optical observations
  19. HETE detection of burst from SGR1806-20
  20. GRB030329 -- RATAN-600 data in April-May
  21. GRB 021206, Radio afterglow candidate
  22. GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
  23. GRB030329, SPM optical observations (Correction of GCN2075 R band)
  24. GRB 030528: Optical Observations
  25. GRB030528(=H2724): Observations with the Chandra X-ray Observatory
  26. GRB030329, SPM optical observations
  27. GRB 030519B: optical observations.
  28. MASTER: optical observation GRB030601
  29. GRB030528(=H2724): Revised SXC Localization
  30. GRB 030329: optical observations
  31. GRB 030528, Teramo optical observation
  32. GRB 030528 Bisei optical observation
  33. GRB030528 (H2724): A long GRB localized by HETE
  34. GRB 030329: Optical Observations
  35. GRB 030528: Optical observations at RIKEN
  36. GRB 030528 (=H2724) Kyoto optical observation
  37. GRB 030416: Optical Observations
  38. GRB 030329: optical photometry at various french observatories
  39. GRB 030329: optical photometry at Belesta observatory (France)
  40. GRB030329, Optical observations
  41. GRB 030329: HST ACS Observations of the Host
  42. GRB 030329 Optical Observations
  43. GRB030329: XMM-Newton observation
  44. GRB030324: Further Observations of the Candidate Optical Afterglow
  45. GRB030519B (=H2716): Peak Fluxes, Fluences, and Energy Spectrum
  46. GRB 030418: Second Epoch Optical Observations with Magellan
  47. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  48. GRB 030329: Optical limit (contemporaneous imaging)
  49. GRB030329: RTT150 optical observations
  50. GRB030329, BVRI photometry
  51. GRB030429, refiend optical brightness
  52. GRB 030329: Optical limit (contemporaneous photography)
  53. GRB030418, BVRcIc field photometry
  54. GRB030429, BVRcIc field photometry
  55. GRB030429: RTT150 optical obs., correction to GCN 2208
  56. GRB 030329: High-Resolution Spectroscopy of the Host
  57. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  58. GRB030418 (=H2686): A Long, X-Ray-Rich GRB Localized by the HETE WXM
  59. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  60. GRB030429: RTT150 optical observations, a possible host galaxy
  61. GRB030329: RTT150 optical observations and upper limit for a host
  62. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  63. GRB030501, optical observation
  64. GRB030501 observation report
  65. GRB030329: RTT150 optical observations and upper limit for a host
  66. GRB 030429: Radio Observations
  67. GRB 030429: redshift from VLT spectroscopy
  68. GRB 030329 Optical Observations
  69. GRB030328, optical observation
  70. GRB 030329, BVRI photometry
  71. GRB030429: Optical Observations
  72. GRB030501: TAROT candidate afterglow present in archival images
  73. GRB030429, possible optical counterpart
  74. GRB030425: CrAO optical observation
  75. GRB 030329 Oprical observations in Rozhen observatory
  76. GRB 030324: Radio Observations
  77. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  78. GRB030329, SPM optical observations (Correction)
  79. GRB030329, SPM optical observations
  80. GRB 030329: Spectral Evolution of SN 2003dh
  81. Optical Observations of GRB 030418 with Magellan
  82. GRB 030329: optical spectropolarimetry at VLT
  83. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  84. GRB030329: optical polarization
  85. GRB030329, optical observation
  86. ROTSE-III prompt optical detections of GRB 030418
  87. GRB030418: Upper limits from recent and historical observations.
  88. GRB 030418: Optical afterglow
  89. GRB 030418: Finder for afterglow candidate
  90. GRB 030418: Optical afterglow candidate
  91. GRB 030329 OT position
  92. GRB030329: Optical Observations
  93. OT GRB 030329: early UBVRcIc spectral evolution
  94. GRB030329, UBVRI polarimetry, R-polarization
  95. GRB 030329: SARA Optical Observations
  96. OT GRB 030329: early spectrum
  97. GRB030324: Candidate Optical Afterglow (Erratum)
  98. GRB030324: Candidate Optical Afterglow
  99. GRB 030413: Optical Observations
  100. GRB 030329 Rc observations

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