{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2012:B2G34MAXFGUDILNOLM3EMMLCIP","short_pith_number":"pith:B2G34MAX","canonical_record":{"source":{"id":"1205.1969","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2012-05-09T12:52:50Z","cross_cats_sorted":[],"title_canon_sha256":"378c8099ef17a5bcd96c633036f74d3363d4616e06d64922b835058ca0c69151","abstract_canon_sha256":"adf0f321abf09b5acf87c72f16805860de6a693f5ab045095c01744d21d3dbb0"},"schema_version":"1.0"},"canonical_sha256":"0e8dbe301729a8342dae5b3646316243fc6948a62051feaa74396254b43b0fc3","source":{"kind":"arxiv","id":"1205.1969","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1205.1969","created_at":"2026-05-18T01:57:36Z"},{"alias_kind":"arxiv_version","alias_value":"1205.1969v1","created_at":"2026-05-18T01:57:36Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1205.1969","created_at":"2026-05-18T01:57:36Z"},{"alias_kind":"pith_short_12","alias_value":"B2G34MAXFGUD","created_at":"2026-05-18T12:26:58Z"},{"alias_kind":"pith_short_16","alias_value":"B2G34MAXFGUDILNO","created_at":"2026-05-18T12:26:58Z"},{"alias_kind":"pith_short_8","alias_value":"B2G34MAX","created_at":"2026-05-18T12:26:58Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2012:B2G34MAXFGUDILNOLM3EMMLCIP","target":"record","payload":{"canonical_record":{"source":{"id":"1205.1969","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2012-05-09T12:52:50Z","cross_cats_sorted":[],"title_canon_sha256":"378c8099ef17a5bcd96c633036f74d3363d4616e06d64922b835058ca0c69151","abstract_canon_sha256":"adf0f321abf09b5acf87c72f16805860de6a693f5ab045095c01744d21d3dbb0"},"schema_version":"1.0"},"canonical_sha256":"0e8dbe301729a8342dae5b3646316243fc6948a62051feaa74396254b43b0fc3","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:57:36.120434Z","signature_b64":"O1penFQQddOJzNF+oo3Y1Q06zuPGc9jxgHuZPjl+/Gm4k06Z3GssKIW0KU3oPQh9YXaysUWJctXwFDOA/di1Dg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"0e8dbe301729a8342dae5b3646316243fc6948a62051feaa74396254b43b0fc3","last_reissued_at":"2026-05-18T01:57:36.119657Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:57:36.119657Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1205.1969","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:57:36Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"+lJJUWkJ29tarDEcqwEDc3cK9jn8WAsMAzuH8Z8fIwrXdOwx1xdOmNfwV6y4fhxtRDqOBTYfh7UQtMyjxHdQBg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T11:52:26.044937Z"},"content_sha256":"5e42e8efbf0a4cb64c188c97b93e4bc78e8899e2428ae21e9ca6e03aa09abc8d","schema_version":"1.0","event_id":"sha256:5e42e8efbf0a4cb64c188c97b93e4bc78e8899e2428ae21e9ca6e03aa09abc8d"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2012:B2G34MAXFGUDILNOLM3EMMLCIP","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Absolute detector calibration using twin beams","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"quant-ph","authors_text":"Jan Perina Jr, Martin Hamar, Ondrej Haderka, Vaclav Michalek","submitted_at":"2012-05-09T12:52:50Z","abstract_excerpt":"A method for the determination of absolute quantum detection efficiency is suggested based on the measurement of photocount statistics of twin beams. The measured histograms of joint signal-idler photocount statistics allow to eliminate an additional noise superimposed on an ideal calibration field composed of only photon pairs. This makes the method superior above other approaches presently used. Twin beams are described using a paired variant of quantum superposition of signal and noise."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1205.1969","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:57:36Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"AikoszPVkkja/o4PXkbc7WiDV9QeA8PeUZNStir0ehEBQ7puwvOo7dlwikGIaxvvlW9qjQ15a5+cte0gS5ZJAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T11:52:26.045640Z"},"content_sha256":"cf89f0861102776806bced9832accc46947c728b804c00b16e3afa8d610febfd","schema_version":"1.0","event_id":"sha256:cf89f0861102776806bced9832accc46947c728b804c00b16e3afa8d610febfd"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/B2G34MAXFGUDILNOLM3EMMLCIP/bundle.json","state_url":"https://pith.science/pith/B2G34MAXFGUDILNOLM3EMMLCIP/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/B2G34MAXFGUDILNOLM3EMMLCIP/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-05-25T11:52:26Z","links":{"resolver":"https://pith.science/pith/B2G34MAXFGUDILNOLM3EMMLCIP","bundle":"https://pith.science/pith/B2G34MAXFGUDILNOLM3EMMLCIP/bundle.json","state":"https://pith.science/pith/B2G34MAXFGUDILNOLM3EMMLCIP/state.json","well_known_bundle":"https://pith.science/.well-known/pith/B2G34MAXFGUDILNOLM3EMMLCIP/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2012:B2G34MAXFGUDILNOLM3EMMLCIP","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"adf0f321abf09b5acf87c72f16805860de6a693f5ab045095c01744d21d3dbb0","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2012-05-09T12:52:50Z","title_canon_sha256":"378c8099ef17a5bcd96c633036f74d3363d4616e06d64922b835058ca0c69151"},"schema_version":"1.0","source":{"id":"1205.1969","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1205.1969","created_at":"2026-05-18T01:57:36Z"},{"alias_kind":"arxiv_version","alias_value":"1205.1969v1","created_at":"2026-05-18T01:57:36Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1205.1969","created_at":"2026-05-18T01:57:36Z"},{"alias_kind":"pith_short_12","alias_value":"B2G34MAXFGUD","created_at":"2026-05-18T12:26:58Z"},{"alias_kind":"pith_short_16","alias_value":"B2G34MAXFGUDILNO","created_at":"2026-05-18T12:26:58Z"},{"alias_kind":"pith_short_8","alias_value":"B2G34MAX","created_at":"2026-05-18T12:26:58Z"}],"graph_snapshots":[{"event_id":"sha256:cf89f0861102776806bced9832accc46947c728b804c00b16e3afa8d610febfd","target":"graph","created_at":"2026-05-18T01:57:36Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"A method for the determination of absolute quantum detection efficiency is suggested based on the measurement of photocount statistics of twin beams. The measured histograms of joint signal-idler photocount statistics allow to eliminate an additional noise superimposed on an ideal calibration field composed of only photon pairs. This makes the method superior above other approaches presently used. Twin beams are described using a paired variant of quantum superposition of signal and noise.","authors_text":"Jan Perina Jr, Martin Hamar, Ondrej Haderka, Vaclav Michalek","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2012-05-09T12:52:50Z","title":"Absolute detector calibration using twin beams"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1205.1969","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:5e42e8efbf0a4cb64c188c97b93e4bc78e8899e2428ae21e9ca6e03aa09abc8d","target":"record","created_at":"2026-05-18T01:57:36Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"adf0f321abf09b5acf87c72f16805860de6a693f5ab045095c01744d21d3dbb0","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"quant-ph","submitted_at":"2012-05-09T12:52:50Z","title_canon_sha256":"378c8099ef17a5bcd96c633036f74d3363d4616e06d64922b835058ca0c69151"},"schema_version":"1.0","source":{"id":"1205.1969","kind":"arxiv","version":1}},"canonical_sha256":"0e8dbe301729a8342dae5b3646316243fc6948a62051feaa74396254b43b0fc3","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"0e8dbe301729a8342dae5b3646316243fc6948a62051feaa74396254b43b0fc3","first_computed_at":"2026-05-18T01:57:36.119657Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:57:36.119657Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"O1penFQQddOJzNF+oo3Y1Q06zuPGc9jxgHuZPjl+/Gm4k06Z3GssKIW0KU3oPQh9YXaysUWJctXwFDOA/di1Dg==","signature_status":"signed_v1","signed_at":"2026-05-18T01:57:36.120434Z","signed_message":"canonical_sha256_bytes"},"source_id":"1205.1969","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:5e42e8efbf0a4cb64c188c97b93e4bc78e8899e2428ae21e9ca6e03aa09abc8d","sha256:cf89f0861102776806bced9832accc46947c728b804c00b16e3afa8d610febfd"],"state_sha256":"ecade0905e27f30d0e96325fbef03a0876850744d947968a1269d898f2f17bf9"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"KF65pCbnzR7cxJD3yn/dKi6eofr1Gfopx1uVkdrxGFfRecagd9arJOK8Jaqq4McJP3tgLbppXtQiGAnxb1lCBw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-25T11:52:26.049098Z","bundle_sha256":"1416539f012b6e4b99770c65a0a87a65890b3c6c14a06fe5dc57a5c1a9c3942b"}}