The Carnegie Supernova Project: The Low-Redshift Survey

Alexei V. Filippenko; Barry F. Madore; Carlos Contreras; D. C. Murphy; Gast\'on Folatelli; Jos\'e Maza; Mario Hamuy; Mark M. Phillips; Miguel Roth; Nicholas B. Suntzeff

RECORD

The Carnegie Supernova Project: The Low-Redshift Survey

Mario Hamuy, Gastón Folatelli, Nidia I. Morrell, Mark M. Phillips, Nicholas B. Suntzeff, S. E. Persson, Miguel Roth, Sergio Gonzalez

show 10 more authors

Wojtek Krzeminski, Carlos Contreras, Wendy L. Freedman, D. C. Murphy, Barry F. Madore, P. Wyatt, José Maza, Alexei V. Filippenko, Weidong Li, P. A. Pinto

Astrophysics · Submitted 1 Dec 2005

abstract compiled · 2026-09-23 · no language-model review

The authors' main claim The low-redshift portion of the Carnegie Supernova Project (CSP) seeks to remedy this situation by providing photometry and spectrophotometry of a large sample of supernovae taken on telescope/filter/detector systems that are well understood and well characterized.

how it is stated · asserted 0.92 read the record →

Comment (0) Read on arXiv ↗

Cite ▾

arXiv IDastro-ph/0512039 (version 1)

Pith IDSZ6TM4LQ, Pith's permanent record of this paper and its review

CitationAlexei V. Filippenko, Barry F. Madore, Carlos Contreras, D. C. Murphy, Gast\'on Folatelli, Jos\'e Maza, Mario Hamuy, Mark M. Phillips, Miguel Roth, Nicholas B. Suntzeff, Nidia I. Morrell, P. A. Pinto, P. Wyatt, S. E. Persson, Sergio Gonzalez, Weidong Li, Wendy L. Freedman, Wojtek Krzeminski. "The Carnegie Supernova Project: The Low-Redshift Survey." arXiv:astro-ph/0512039 (2005). https://pith.science/paper/SZ6TM4LQ

Claim paper

The compiled record

The paper's own sentences, arranged. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.

Open the compiled record

Compiled by classifier-1.13.0 via TypeSafe API, question bank abstract-p1-20260923, 2026-09-23: 1 request, 7,004 input tokens.

What the abstract itself states, as probabilities: claims first 0.06 · states limitation 0.52 · human participants 0.03 · controlled comparison 0.02 · randomized assignment 0.01 · states quantitative result 0.69 · compares with prior results 0.41 · mentions code or data availability 0.05.

The abstract, sentence by sentence

arXiv listing abstract v1. Results and the main claim are underlined; show every role.

Supernovae are essential to understanding the chemical evolution of the Universe. Type Ia supernovae also provide the most powerful observational tool currently available for studying the expansion history of the Universe and the nature of dark energy. Our basic knowledge of supernovae comes from the study of their photometric and spectroscopic properties. However, the presently available data sets of optical and near-infrared light curves of supernovae are rather small and/or heterogeneous, and employ photometric systems that are poorly characterized. Similarly, there are relatively few supernovae whose spectral evolution has been well sampled, both in wavelength and phase, with precise spectrophotometric observations. The low-redshift portion of the Carnegie Supernova Project (CSP) seeks to remedy this situation by providing photometry and spectrophotometry of a large sample of supernovae taken on telescope/filter/detector systems that are well understood and well characterized. During a five-year program which began in September 2004, we expect to obtain high-precision u'g'r'i'BVYJHKs light curves and optical spectrophotometry for about 250 supernovae of all types. In this paper we provide a detailed description of the CSP survey observing and data reduction methodology. In addition, we present preliminary photometry and spectra obtained for a few representative supernovae during the first observing campaign.

background contribution method result interpretation main claim

What the classifier reports for each sentence. The number is the probability it gave the label.
#	sentence	role	the authors' own work	states the main conclusion	strength
s0	Supernovae are essential to understanding the chemical evolution of the Universe.	background 1.00	0.04	0.03	asserted 1.00
s1	Type Ia supernovae also provide the most powerful observational tool currently available for studying the expansion history of the Universe and the nature of dark energy.	background 1.00	0.04	0.04	asserted 1.00
s2	Our basic knowledge of supernovae comes from the study of their photometric and spectroscopic properties.	background 1.00	0.04	0.02	asserted 1.00
s3	However, the presently available data sets of optical and near-infrared light curves of supernovae are rather small and/or heterogeneous, and employ photometric systems that are poorly characterized.	gap 0.97	0.08	0.03	asserted 1.00
s4	Similarly, there are relatively few supernovae whose spectral evolution has been well sampled, both in wavelength and phase, with precise spectrophotometric observations.	gap 0.97	0.09	0.02	asserted 1.00
s5	The low-redshift portion of the Carnegie Supernova Project (CSP) seeks to remedy this situation by providing photometry and spectrophotometry of a large sample of supernovae taken on telescope/filter/detector systems that are well understood and well characterized.	contribution 0.96	0.40	0.14	asserted 0.92
s6	During a five-year program which began in September 2004, we expect to obtain high-precision u'g'r'i'BVYJHKs light curves and optical spectrophotometry for about 250 supernovae of all types.	contribution 0.47	0.53	0.06	asserted 0.54
s7	In this paper we provide a detailed description of the CSP survey observing and data reduction methodology.	contribution 0.86	0.79	0.05	asserted 0.99
s8	In addition, we present preliminary photometry and spectra obtained for a few representative supernovae during the first observing campaign.	contribution 0.59	0.96	0.07	asserted 1.00

What kind of paper the classifier reports this is: method or tool 0.54 · evidence from observation or experiment 1.00.

What was examined, and what was not

sources read

arXiv listing abstract v1

not examined

full text
figures and tables
references and citing sentences
relations to other papers

levels run

P abstract

not run

S sections
T body sentences
C citations
R cross-paper relations

Every quoted sentence on this record is the authors'. Every label is from Pith's closed vocabulary, with the probability shown beside it. Every number in the measurements table is the authors', checked by code. Record as JSON

The paper

Original abstract

Supernovae are essential to understanding the chemical evolution of the Universe. Type Ia supernovae also provide the most powerful observational tool currently available for studying the expansion history of the Universe and the nature of dark energy. Our basic knowledge of supernovae comes from the study of their photometric and spectroscopic properties. However, the presently available data sets of optical and near-infrared light curves of supernovae are rather small and/or heterogeneous, and employ photometric systems that are poorly characterized. Similarly, there are relatively few supernovae whose spectral evolution has been well sampled, both in wavelength and phase, with precise spectrophotometric observations. The low-redshift portion of the Carnegie Supernova Project (CSP) seeks to remedy this situation by providing photometry and spectrophotometry of a large sample of supernovae taken on telescope/filter/detector systems that are well understood and well characterized. During a five-year program which began in September 2004, we expect to obtain high-precision u'g'r'i'BVYJHKs light curves and optical spectrophotometry for about 250 supernovae of all types. In this paper we provide a detailed description of the CSP survey observing and data reduction methodology. In addition, we present preliminary photometry and spectra obtained for a few representative supernovae during the first observing campaign.

Human review

How Pith checks papers → · Full audit of this paper →

References

Forward citations

Cited by 6 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

An improved standardization framework for Type II-P supernovae using a hierarchical Bayesian approach
astro-ph.CO 2026-09 conditional novelty 6.0 of 10

A hydrogen line-ratio correction plus a hierarchical Bayesian analysis reduces Type II-P supernova distance scatter to 0.18 mag and measures H0 = 70.6 +4.5 -4.3 km/s/Mpc with statistical-only uncertainties.
Leveraging SN Ia spectroscopic similarity to improve the measurement of $H_0$
astro-ph.CO 2023-05 conditional novelty 6.0 of 10

Spectroscopic similarity between Type Ia supernovae reduces their standardized luminosity scatter and tightens the local Hubble constant to 73.29 ± 0.90 km/s/Mpc, raising the tension with Planck to 5.7σ.
The type Ia supernova 2023vjh: a peculiar 1991bg-like SN with unusually faint light curves
astro-ph.HE 2026-07 accept novelty 5.0 of 10

SN 2023vjh is an unusually faint 91bg-like SN Ia whose light curves and colors suggest possible CSM extinction despite minimal host interstellar dust signatures.
SN2025aico: An Interesting Case Of $^{56}$Ni Mixing, Ejecta Asymmetries, and Dust Formation in a Type IIb Supernova
astro-ph.HE 2026-09 conditional novelty 4.0 of 10

A densely observed Type IIb supernova shows layered ejecta, limited outward 56Ni mixing inferred from a three-phase helium velocity evolution, asymmetric explosion geometry, and remarkably early carbon dust formation.
Late Time Dynamical Dark Energy and the CMB-Distance Ladder Tension
astro-ph.CO 2026-07 conditional novelty 4.0 of 10

The SNIa absolute-magnitude tension between the distance ladder (−19.204) and CMB+ΛCDM (−19.430) is independent of late-time expansion history, and DESI's w0–wa dark-energy hints shift H0 by only ~0.3–0.4 km/s/Mpc.

Show 1 more citing papers

SN 2023rve: A Type II Supernova with No Nebular Oxygen
astro-ph.HE 2026-06 unverdicted novelty 4.0 of 10

SN 2023rve exhibits absent [O I] nebular lines with inferred 14-18 solar mass progenitor, 0.27e51 erg explosion energy, and 0.0064 solar mass nickel, possibly indicating partial fallback.

How later papers used it

56 later papers cite it

Evidence: substantial. 28 of the citing papers share no author with it, and 7 of those carry a confident label from Pith's citation classifier.

Pith read 19 of the 69 citing sentences, choosing only those whose citation markers point at this paper alone, and wrote the paraphrases from them. The summary, the counts, the evidence level, the links and the quotes come from code; the summary counts the papers listed below. A later paper is listed under a label when Pith's citation classifier gives one of its sentences that label at probability 0.8 or more (0.95 for support), Pith's reading finds that the citing paper itself did it, and a second check confirms the paraphrase against the sentence. This section lists uses only. It does not list criticism or disagreement, so their absence here says nothing about how the paper has been received. Papers that share an author with this one are listed apart, under "By the same authors". A quote is the citing authors' own sentence, shown when their paper's licence is CC BY, CC BY-SA or CC0. JSON

3 later papers by other authors are listed below: 2 used its method or tool and 1 used its data or values. 5 more papers by the same authors are listed: 4 used its method or tool and 1 used its data or values.

Uses its method or tool 6 of 9 papers with this label · 4 by the same authors

Applied a linearity correction from this paper to all the Swope (SiTe3) images to increase the range of unsaturated stars.

C,T1,T2: A complementary method to detect Multiple Populations with the Washington filter system (2022) · 0.99 · paraphrased: the licence does not allow quoting
Corrected all frames for linearity before flat-fielding, following the recipe discussed in this paper.

A new look at Sco OB1 association with Gaia DR2 (2020) · 1.00 · paraphrased: the licence does not allow quoting

By the same authors

Reduced its optical spectra using standard iraf packages and methods described in this paper.

A Tale of Two Type Ia Supernovae: The fast-declining siblings SNe 2015bo and 1997cn (2021) (same authors) · 1.00 · paraphrased: the licence does not allow quoting
The spectra from APO and Baade were reduced using standard iraf[The Image Reduction and Analysis Facility (iraf) is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation.] packages with the methods as described in [ref] and [ref] .

Fast and Not-so-Furious: Case Study of the Fast and Faint Type IIb SN 2021bxu (2023) (same authors) · Spectroscopy · 1.00
The IMACS Baade spectra were reduced using standard methods and IRAF routines [IRAF was distributed by the National Optical Astronomy Observatory which was operated by the Association of Universities for Research in Astronomy (AURA) under cooperative agreement with the National Science Foundation.], as described in [ref] .

Characterizing the Rapid Hydrogen Disappearance in SN2022crv: Evidence of a Continuum between Type Ib and IIb Supernova Properties (2023) (same authors) · Spectroscopic Data Reduction · 1.00
Performed data reduction for IMACS using standard iraf packages and the method described in this paper.

Discovery and Follow-up of ASASSN-23bd (AT 2023clx): The Lowest Redshift and Least Luminous Tidal Disruption Event To Date (2024) (same authors) · 1.00 · paraphrased: the licence does not allow quoting

Uses its data or values 2 of 14 papers with this label · 1 by the same authors

Adopted Y=0.0 from this paper.

The Iron Yield of Core-collapse Supernovae (2022) · 0.98 · paraphrased: the licence does not allow quoting

By the same authors

Used the Carnegie Supernova Project-I sample from this paper, with optical and near-infrared light curves in a well-understood photometric system.

Observed Type II supernova colours from the Carnegie Supernova Project-I (2018) (same authors) · 0.92 · paraphrased: the licence does not allow quoting

How the literature uses it

10 arXiv papers cite this in 12 sentences

Each citing sentence is taken from the citing paper's LaTeX source and typed by Pith's classifier. A label appears at probability 0.8 or more (0.95 for support), a contest at 0.7 or more; the quoted words are the citing authors'. How each label was checked · JSON

Papers citing it · 7 sentences without a confident label

Uses its data or values 1 paper

The source publications are mostly the official data releases of the main surveys that constitute the baseline sample, including CFA [ref] , LOSS/BSNIP [ref] , CSP [ref] , SDSS [ref] , Foundation [ref] , and PS1 [ref] .

Leveraging SN Ia spectroscopic similarity to improve the measurement of $H_0$ · Spectra · 0.96

Cites it as background 4 papers

[ref] ; * the Perth Automated SN Search [ref] ; * the Mount Stromlo Abell Cluster Supernova Search (MSACSS; [ref] ); * the Wise Observatory Optical Transients Search (WOOTS; [ref] ); * the CfA Supernova search [ref] ; * the Seoul National University SN Search (SNUSS; [ref] ); * the European SN Cosmology Consortium (ESCC; [ref] ); * the QUEST survey [ref] ; * the Nearby Galaxies SN Search (NGSS; [ref] ); * the EROS Nearby SN Search (EROSNSS; [ref] ); * the Beijing Astronomical Observatory SN Survey (BAOSS; [ref] ); * the All-sky Southern Supernova Search [ref] ; * the UK Nova/Supernova Patrol [ref] ; * the Super Livermore Optical Transient Imaging System (Super-LOTIS; [ref] ); * GOODS HST SN Search [ref] ; * The Carnegie Supernova Project (CSP; [ref] ); * the Nearby Supernova Factory [ref] ; * the CFHT Supernova Legacy Survey (SNLS; [ref] ); * SkyMapper [ref] ; * the ESSENCE Supernova Sur

Supernovae and Gaia · Modern and future SN searches · 0.97
NIR SN Ia samples and analyses have been performed by projects such as the Carnegie Supernova Project [ref] through CSP-I [ref] and CSP-II [ref] , CfA [ref] , RATIR [ref] , SweetSpot [ref] , RAISIN [ref] , and are ongoing in the VISTA Extragalactic Infrared Legacy Survey (VEILS) and the Supernovae in the InfRAred Avec Hubble (SIRAH) projects.

The DEHVILS Survey Overview and Initial Data Release: High-Quality Near-Infrared Type Ia Supernova Light Curves at Low Redshift · Introduction · 0.99
From SNe Ia observational data one could measure cosmological parameters describing the homogeneous expansion of the universe through measurements of the luminosity distance such as matter and dark energy densities and equation of state parameters [ref] .

Data compression of measurements of peculiar velocities of Supernovae Ia · Introduction · 0.83

Discussion

Know something about this paper? Leave a comment, or highlight any passage above to comment on it.