Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant

Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant Adam G. Riess et al. (High-z Supernova Search Team)

Tag layer of the DHSS Meta-Tagging Project. The article text is reproduced from the staged copy named in sourceDesc and is not altered; the tags are held separately in standOff so that overlapping and nested spans are preserved.

Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant 1998 The Astronomical Journal / arXiv 10.1086/300499 astro-ph/9805201 riess1998-accelerating-universe riess1998-accelerating-universe.txt, the project's staged copy 85d4610bfcebbfa84c1c8e6e0f3b98b722f20634 arxiv-open astronomy

the paper's own words

the tag layer; a sentence written by the tagger about the paper, always anchored to a quotation but not itself a quotation

0 spans located by searching the stored text for the quote's exact words, allowing any whitespace between them existence Quotation withheld because this record is not cleared for redistribution. acceleration of the cosmic expansion Quotation withheld because this record is not cleared for redistribution. observational-study observational-study Quotation withheld because this record is not cleared for redistribution. mechanisms A PARAMETER THAT CANNOT BE USED BECAUSE IT VARIES IS REPLACED BY VARYING IT DELIBERATELY: limiting magnitudes vary FROM FRAME TO FRAME, NIGHT TO NIGHT, AND FILM TO FILM, SO IT IS DIFFICULT TO USE THE ACTUAL DETECTION LIMITS in the simulation - NEVERTHELESS simulations were run VARYING the limiting magnitude, and THIS DOES NOT CHANGE THE RESULTS SIGNIFICANTLY. An unusable measurement becomes a swept parameter, and the sweep is the answer to its own unusability about this quote: ON THIS FILE'S CONDITION, because it bears on every span from it. riess1998 has NO glyph codes and my first damage measurement therefore returned 1% and called it clean. The damage is DAMAGE SHAPE 8, the spurious intra-word space - "ligh t curve", "constrain ts", "treatme nt", "supernov a", "the c omposition" - which no character marks and for which an earlier note of ours showed there is no usable detector. Every span merged from this record was verified BY READING, word by word; the yield from 576 candidate sentences was seven. Quotation withheld because this record is not cleared for redistribution. mechanisms A MORE REALISTIC PRIOR IS ADOPTED, AND THE WORD `REALISTIC` IS THE JUSTIFICATION: a MORE REALISTIC A PRIORI PROBABILITY DISTRIBUTION for extinction HAS BEEN UTILIZED, taken from another group's calculations. The same physical quantity, in the same year, is treated the opposite way by perlmutter1999, which describes the realistic option and declines it in favour of a conservative one Quotation withheld because this record is not cleared for redistribution. mechanisms A CORRECTION'S ASSUMPTION IS STATED AND CONTRADICTED IN THE SAME SENTENCE: such a K-correction ASSUMES that the spectral energy distribution of all SNe Ia OF A GIVEN AGE IS HOMOGENEOUS - YET IT HAS BEEN SHOWN otherwise, with a list of references. The step is used, its premise is named, and the premise is reported false, in one breath Quotation withheld because this record is not cleared for redistribution. mechanisms A SYSTEMATIC ERROR IS MEASURED WITH SYNTHETIC OBJECTS AND THEN SUBTRACTED, AND THE RESULT IS CALLED UNBIASED: a correction BASED ON THE SYSTEMATIC ERROR DETERMINED FROM THE ARTIFICIAL STARS was applied to the measured magnitude TO YIELD AN UNBIASED ESTIMATE. The word `unbiased` is earned by a procedure on objects that were never there Quotation withheld because this record is not cleared for redistribution. mechanisms THE SYNTHETIC OBJECTS ARE MATCHED TO THE REAL ONES ON TWO NAMED PROPERTIES: Quotation withheld. What makes the simulation stand in for the measurement is an equality on exactly two attributes, and they are listed about this quote: RE-SLICED: ending at "(Schmidt et al." opened a bracket the span never closed - caught by the unclosed-opener check, which is the mirror of an earlier note of ours and was built three hours ago. Quotation withheld because this record is not cleared for redistribution. mechanisms A CLASSIFICATION IS FIXED BY COMPARISON TO EXEMPLARS WHOSE OWN PROPERTY COMES FROM A DIFFERENT MEASUREMENT: final spectral classification IS OPTIMIZED BY COMPARING the observed spectrum to WELL-OBSERVED SPECTRA of the same class AT THE SAME AGE AS DETERMINED FROM THE LIGHT CURVES. The comparison set is selected using a quantity measured by another instrument entirely Quotation withheld because this record is not cleared for redistribution. mechanisms COMPARABILITY BETWEEN TWO EXPERIMENTS IS DEFERRED TO FUTURE WORK, AND THE CONDITION IS NAMED: Quotation withheld The present comparison is therefore not claimed to be meaningful, and what would make it so is stated Quotation withheld because this record is not cleared for redistribution. residual noise from sky lines remains in the spectra what this limits: the spectral typing and redshifts: RESIDUAL NOISE FROM THE SKY LINES REMAINS Quotation withheld because this record is not cleared for redistribution. systematic uncertainties in the Cepheid distance scale affect the age estimate about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Update, 15 September 2026: CLEARED evidence status='quote-not-in-current-staged-text' - the quote now locates in the current staged text, so the condition the marker recorded no longer holds. Quotation withheld because this record is not cleared for redistribution. A modest amount of grey interstellar extinction cannot be excluded by these data. what this limits: the acceleration conclusion, against its main rival: WITH THE OBSERVATIONS PRESENTED HERE, WE CANNOT RULE OUT THIS MODEST AMOUNT OF GREY INTERSTELLAR EXTINCTION Quotation withheld because this record is not cleared for redistribution. The high-redshift sample is too small to test whether light-curve-shape relations evolve with look-back time. what this limits: any claim that light-curve-shape relations do not evolve: PRESENTLY, OUR SAMPLE IS TOO SMALL TO MAKE SUCH A TEST MEANINGFUL Quotation withheld because this record is not cleared for redistribution. The KS comparison of low- and high-redshift light-curve decline rates is not statistically significant given the sample size. what this limits: the KS comparison of decline rates: A KOLMOGOROV-SMIRNOV TEST SHOWS NO SIGNIFICANT DIFFERENCE ... BUT THE SAMPLE IS TOO SMALL TO BE STATISTICALLY SIGNIFICANT - the null is uninformative Quotation withheld because this record is not cleared for redistribution. Evolution of the supernova population remains a serious unresolved concern. what this limits: the whole cosmological inference: EVOLUTION REMAINS A SERIOUS CONCERN WHICH CAN ONLY BE EASED AND PERHAPS UNDERSTOOD BY FUTURE STUDIES Quotation withheld because this record is not cleared for redistribution. The discrepancy between the two light-curve fitting methods must be carried as a systematic uncertainty. what this limits: every cosmological constraint quoted: WE MUST CONSIDER THE DIFFERENCE BETWEEN THE COSMOLOGICAL CONSTRAINTS REACHED FROM THE TWO FITTING METHODS TO BE A SYSTEMATIC UNCERTAINTY - the analysis choice moves the answer, so the spread is carried Quotation withheld because this record is not cleared for redistribution. The result is limited by systematic rather than statistical errors. what this limits: the precision of the headline result: OUR DETECTION OF A COSMOLOGICAL CONSTANT IS NOT LIMITED BY STATISTICAL ERRORS BUT BY SYSTEMATIC ONES Quotation withheld because this record is not cleared for redistribution. Remaining systematic uncertainties require further study. what this limits: the same scope as limitations[7]: FURTHER STUDIES ARE NEEDED TO DETERMINE THE POSSIBLE INFLUENCE OF ANY REMAINING SYSTEMATIC UNCERTAINTIES Quotation withheld because this record is not cleared for redistribution. The headline quantity exists only relative to an assumed model of what causes it. what this limits: the deceleration parameter reported here: because it is defined at the current epoch while the supernovae span a wide range of redshift, its value can only be determined within the context of a model for its origin Quotation withheld because this record is not cleared for redistribution. The nearby comparison sample was cut to match the observing window available at high redshift. what this limits: the comparison between nearby and high-redshift supernovae: the nearby sample was limited to light curves beginning no later than about five days after B maximum, to match the age by which the high-redshift observations ended Quotation withheld because this record is not cleared for redistribution. The colour correction needs a quantity the survey must itself measure well. what this limits: the K-corrections applied to these magnitudes: differences in supernova colour at a fixed phase would alter the appropriate correction, so each supernova's colour must be known precisely Quotation withheld because this record is not cleared for redistribution. Bayesian statistical inference and Monte Carlo simulation applied to Type Ia supernova data to infer the expansion history and cosmic acceleration about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution. the supernova distance analysis run twice, with and without the most distant object, whose extinction and classification are uncertain eliminates: the entire acceleration result resting on one object that is both the most informative and the least certain in the sample · outcome (stated by the tagger, no quotation): held Quotation withheld because this record is not cleared for redistribution. cosmological constant cosmological constant Quotation withheld because this record is not cleared for redistribution. K-correction K-correction Quotation withheld because this record is not cleared for redistribution. color color Quotation withheld because this record is not cleared for redistribution. progenitor age progenitor age Quotation withheld because this record is not cleared for redistribution. light curve shape light curve shape Quotation withheld because this record is not cleared for redistribution. a more realistic a priori probability distribution for extinction → the extinction prior this paper ADOPTS THE SAME ADJECTIVE, THE SAME PHYSICAL QUANTITY, THE SAME YEAR, OPPOSITE DECISIONS - and no type in the vocabulary can express it. This paper ADOPTS the option it calls more realistic. perlmutter1999-omega-lambda describes the same option for the same quantity as “a less conservative but more realistic narrow prior” and DECLINES it, keeping the conservative one. 'contradicts' would be FALSE: neither team contradicts the other, they weigh the same consideration about the extinction prior and rule differently, and each calls its own reasoning 'more realistic'. All eight edge types assert that a relation HOLDS between two concepts; not one can say that two papers apply one word to opposite choices. Recorded here, per record, with each row quoting only its own paper - the cross-paper half is this paraphrase, checkable by opening perlmutter1999-omega-lambda. This is a NEW use of unhoused-relations: all 67 existing rows describe a relation inside one paper, and this is the first pair that spans two. second case; Quotation withheld because this record is not cleared for redistribution. q0, the deceleration parameter - MODEL-RELATIVE BY CONSTRUCTION: it is defined at the present epoch while the data span a wide range of redshift, so the paper states the value can only be determined inside a model of what produces the deceleration Quotation withheld because this record is not cleared for redistribution. the K-correction - AS A PASSBAND DIFFERENCE: it quantifies the gap between the supernova light falling into a standard filter at zero redshift and the light falling into the filters actually used on a redshifted object, so it is a correction between instruments and not a property of the supernova Quotation withheld because this record is not cleared for redistribution. the nearby sample - TRIMMED TO MATCH THE DISTANT ONE: nearby supernovae were admitted only if their light curves began within about five days of B maximum, because that is the window the high-redshift observations could cover, so the two samples were made comparable by discarding data that existed Quotation withheld because this record is not cleared for redistribution. contradicts → Perlmutter et al. (1997) Quotation withheld because this record is not cleared for redistribution. replicates → High-z Supernova Search Team (Garnavich et al. 1998; Schmidt et al. 1998) Quotation withheld because this record is not cleared for redistribution. builds-on → Garnavich et al. 1998; Schmidt et al. 1998; Riess et al. (1998a) Quotation withheld because this record is not cleared for redistribution. color —causes→ K-correction color K-correction strength of the relation: 1 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span says differences in color WOULD alter the appropriate K-correction; conditional. Quotation withheld because this record is not cleared for redistribution. 10 — new high-redshift SNe Ia observed Quotation withheld because this record is not cleared for redistribution. 0.16 ≤ z ≤ 0.62 — redshift range of the new supernovae Quotation withheld because this record is not cleared for redistribution. 16 + 34 — 16 high-redshift + 34 nearby SNe Ia used for the cosmological fit about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution. q0 < 0 — negative deceleration parameter = the cosmic expansion is accelerating Quotation withheld because this record is not cleared for redistribution. The expansion of the universe is currently accelerating (q0 < 0). Quotation withheld because this record is not cleared for redistribution. cosmological parameters cosmological parameters about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution. redshift redshift Quotation withheld because this record is not cleared for redistribution. luminosity distance luminosity distance Quotation withheld because this record is not cleared for redistribution. standard candle standard candle about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution. deceleration parameter deceleration parameter about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution. Bayesian Bayesian about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution. confidence-interval confidence-interval about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution. correlation correlation about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution. mean mean about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution. sample-size sample-size about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution. statistical-significance statistical-significance about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution. variance variance about this quote: QUOTE RECOVERED FROM THE PAPER'S OWN CHARACTERS. The recorded quote was LETTERS-ONLY IDENTICAL to this stretch of the staged text but not an exact substring of it - spaces, hyphens, ligature glyphs or mathematical operators differed, so it could never anchor. This is the file's own text between the same two letters: not produced by a rule about the damage, copied out of the file. Round-trip checked (the recovered span is letters-only equal to the original) and length-checked. The text as originally recorded is kept in evidence as extracted. Quotation withheld because this record is not cleared for redistribution.

The full text of this article is not redistributable, so it is not included here. The evidence sentences are withheld with it; the tag layer and its grounding status remain. The article itself is at https://doi.org/10.1086/300499.