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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"

32505 results found.

  1. GRB 030429: Radio Observations
  2. GRB 030429: redshift from VLT spectroscopy
  3. GRB 030429: IR photometry with IRSF/SIRIUS
  4. GRB030501B triangulation (single error box)
  5. GRB 030329 Optical Observations
  6. GRB030328, optical observation
  7. GRB 030329, BVRI photometry
  8. GRB030429: Optical Observations
  9. GRB030501: TAROT candidate afterglow present in archival images
  10. GRB 030501: TAROT possible candidate counterpart
  11. IPN triangulation of GRB030501 (IBIS event; annulus)
  12. GRB 030429: confirmation of afterglow candidate
  13. GRB030425: CrAO optical observation
  14. GRB 030329 Oprical observations in Rozhen observatory
  15. GRB 030324: Radio Observations
  16. GRB030329 observed as a sudden ionospheric disturbance (SID)
  17. GRB030329, SPM optical observations
  18. GRB 030329, the review of the sky area in plate archive (1950-1998)
  19. GRB 030329: Spectral Evolution of SN 2003dh
  20. GRB 030329: optical spectropolarimetry at VLT
  21. GRB030329: optical polarization
  22. GRB030329, optical observation
  23. GRB030329: 444 AAVSO Measurements
  24. ROTSE-III prompt optical detections of GRB 030418
  25. GRB030418: Upper limits from recent and historical observations.
  26. GRB 030418: Optical afterglow
  27. GRB 030418: Finder for afterglow candidate
  28. GRB 030329 OT position
  29. GRB030329: Optical Observations
  30. OT GRB 030329: early UBVRcIc spectral evolution
  31. GRB030329, UBVRI polarimetry, R-polarization
  32. GRB 030329: SARA Optical Observations
  33. OT GRB 030329: early spectrum
  34. GRB030329: VR Photometry at TNG
  35. GRB030324: Candidate Optical Afterglow
  36. GRB 030413: Optical Observations
  37. GRB 030329 Rc observations
  38. Superluminal motion in GRB 030329 (Correction)
  39. Superluminal motion in GRB 030329
  40. GRB 030329 and SN 2003dh
  41. GRB030329, optical position
  42. GRB 030329 VLBA Observations
  43. GRB 030329: BVRI photometry at Asiago
  44. GRB 030329, light curve flattens
  45. GRB 030329: VLT V-band photometry
  46. If the SN/GRB connection confirmed
  47. GRB 030329: Supernova Confirmed
  48. GRB030329: RTT150 optical observations
  49. GRB030329: Near Infrared Observations at Gunma
  50. GRB030329: HET spectroscopic monitoring
  51. GRB 030329, color evolution
  52. GRB030328, UBVRcIc field photometry
  53. GRB030329: Optical observcations
  54. GRB030329: BV photographic observations
  55. GRB 030329 Optical observations
  56. GRB 030329, color evolution
  57. GRB 030329: possible color change
  58. GRB030329: RTT150 optical observations
  59. GRB 030329: Supernova Spectrum Emerging
  60. GRB030329: RTT150 optical observation
  61. GRB030329: More AAVSO VR obs
  62. GRB030328: R upper limit after 6 hours by MASTER
  63. GRB 030329: BV photographic observations
  64. GRB 030329: SARA Optical Observations
  65. GRB 030329: SARA Optical Observations
  66. GRB030329, fading resumes
  67. GRB 030329, BVRI photometry
  68. GRB030329: Optical observations
  69. SDSS 0.5m PT observations of GRB030329 (correction)
  70. SDSS 0.5m PT observations of GRB030329
  71. GRB 030329, Optical observations
  72. GRB 030329, nearby galaxies
  73. GRB030329, cessation of fading
  74. GRB030329: final R-band light curve by MASTER
  75. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  76. GRB 030329: Sub-millimeter detection
  77. GRB 030329: SARA Optical Observations
  78. GRB 030329: SARA Optical Observations
  79. OT GRB light curves and SN predictions
  80. GRB030329, optical observation
  81. GRB030329, optical observation
  82. GRB030329, new UBVRcIc field photometry
  83. GRB 030329, light curve and SN prediction
  84. GRB030329: optical observations at Tokyo Tech
  85. GRB 030329: optical observations
  86. GRB030329: multiple re-brightening phases
  87. GRB 030329, BRI photometry
  88. GRB030329: Optical observations at Teramo
  89. GRB030329: more 15GHz observations
  90. Further AAVSO V,B,R observations of GRB030329
  91. GRB 030329: Additional Mt. Laguna Optical Observations
  92. GRB 030329: SARA Optical Observations
  93. GRB 030329: Observations with ANDICAM
  94. GRB030329: Optical observations
  95. GRB 030329: Correction to GCN 2056
  96. GRB 030329: fitting parameters and re-brightening
  97. GRB 030329: KAIT optical photometry
  98. GRB030329 Further RBO Optical Observations
  99. triangulation of GRB 030331 (single error box)
  100. GRB030329 - OT rebrightens

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