JCAP Submission Guide: Timeline & Editorial Fit

Source: JCAP on IOP, Clarivate 2026 JCR release, accessed April 2026.

This is the JCAP-specific structural detail authors most often miss:

JCAP, like sister SISSA journal JHEP, has a strong arXiv-first culture:

• Most submissions are simultaneously posted to arXiv

• Editorial review is aligned with arXiv preprint dissemination

• Authors should plan arXiv posting alongside JCAP submission

The strategic implication: the arXiv-first culture means cosmology + astroparticle community typically discovers JCAP papers through arXiv before formal publication. Authors should ensure arXiv versions are clean and complete.

Three operational signals govern editorial assessment:

1. Cosmology / astroparticle substance. The journal requires substantive cosmology or astroparticle contribution.

2. Methodological rigor. Theoretical, computational, or observational work must be top-tier.

3. SISSA editorial fit. Cosmology + astroparticle theory and phenomenology is the journal's distinctive position.

The SISSA help material makes JCAP different from a generic physics upload. The paper is not routed only by title or editor preference. Authors choose JCAP keywords, and the system uses those keywords to match the submission to an editorial-board member whose expertise and workload fit the paper. That means keyword selection is an editorial signal, not an administrative afterthought.

For a JCAP-bound manuscript, the abstract, keywords, and first two pages should all point to the same lane:

JCAP also states that length should match the information presented and that papers do not normally exceed 50 pages. That matters for submission strategy. A 12-page paper can be too thin if it lacks physical interpretation; a 45-page paper can be reasonable if the calculation, data product, or forecast needs that space. The editor-facing question is whether every section earns its place.

In practice, editors are likely to check three things before reviewer selection. First, does the manuscript belong to the JCAP scope as defined by cosmology and particle astrophysics, not just adjacent physics? Second, do the author's keywords route the paper to the right editorial expertise? Third, does the manuscript meet the strict quality filter the journal says its editors should apply?

The strongest JCAP submissions make that easy. They name the physical question early, identify the data or theory object being advanced, and explain why the result changes a cosmology or astroparticle inference. Weak submissions often have good calculations but leave the editor to infer the cosmological consequence.

Manusights internal analysis identifies one JCAP-specific package risk that the official guidance cannot diagnose from a public checklist: the scope triangle between abstract claim, keyword routing, and first result figure. If those three signals point to different venues, the paper reads as misrouted even when the calculation is technically sound.

Use this quick self-check before upload:

Recent JCAP issues span:

• Dark matter detection and theory

• Dark energy and modified gravity

• Inflation and early-universe physics

• CMB analysis and forecasting (Planck, future experiments)

• Large-scale structure surveys

• Gravitational waves (LIGO, future detectors)

• Neutrino cosmology

• Cosmic-ray and gamma-ray astrophysics

For specific recent papers and DOIs, see JCAP on IOP. Representative recent papers:

• 10.1088/1475-7516/2023/10/045

• 10.1088/1475-7516/2024/04/078

JCAP's flow follows the SISSA/IOP editorial process with an arXiv-first culture. JCAP publishes no overall time-to-decision figure; the stage targets below come from its editorial-workflow help page, which calls them a guideline because scientific quality and relevance have priority over speed.

• Submission: upload through the SISSA Medialab editorial system. The preprint is sent to the editor in charge immediately upon submission, chosen automatically by matching your keywords to the editors' areas of expertise, taking editor workload into account.

• Editor: editors should send new preprints to one or more referees within 5 days. The editor may instead review the paper personally, and the Editorial Office sends up to two reminders if the editor has not acted. If the editor has not reacted within ten days of submission, the scientific director reassigns the paper.

• Referees: referees should accept or decline the assignment within 4 days of the editor's request and review the paper in 4 weeks at most from the date of the editor's review request.

• Decision: the editor makes the decision, generally supported by one or more referees. The editor evaluates scientific quality, originality and relevance, and is asked to apply a strict quality filter.

• Revision: for a major revision authors must provide a new version and a cover letter within 90 days, and for a minor revision within 30 days. Authors may ask the editor in charge to extend these deadlines if strictly necessary.

• Acceptance and publication: accepted papers are typeset in JCAP style and authors get one round of proofreading. IOP Publishing publishes the paper if the authors send no feedback within 7 days of the proofreading notification.

Across cosmology and astroparticle-physics manuscripts targeting Journal of Cosmology and Astroparticle Physics, three recurring decision risks matter most across submissions that JCAP editors filter out at the desk-screen stage. (Per SISSA/IOP published policies, JCAP routes through the jcap.sissa.it portal (NOT IOP IOPscience) with keyword-based editor routing assigning a board member matching the cosmology or astroparticle subfield; criterion for acceptance is high scientific quality + originality + relevance with explicit rejection of routine or "not wrong" work;

ArXiv-first culture means most submissions are simultaneously posted to arXiv and editorial review is aligned with arXiv preprint dissemination; vague or mismatched author keywords create avoidable friction.) Use the three checks below before you open jcap.sissa.it portal upload slot.

Desk-screen failure: cosmology or astroparticle-physics framing thin

Across JCAP-targeted manuscripts, we consistently see authors submit work where the underlying contribution is pure-astrophysics (observational stellar / extragalactic / galactic-dynamics study without cosmological-parameter implications), pure-particle-physics (collider phenomenology, lattice QCD, electroweak theory without astroparticle context), pure-astronomy (instrumentation, observational survey, multi-wavelength catalog without cosmology-question framing), or pure-gravitational-theory (formal general relativity, mathematical relativity, abstract modified-gravity construction without observational connection) with "cosmological implications" added to the abstract as window-dressing.

JCAP handling editors check whether the contribution sits in the journal's actual scope, not just whether it mentions cosmology or astroparticle physics.

The core fit areas are cosmology, astroparticle physics, and the bridge between them. Strong submissions make one of those centers of gravity obvious: early-universe or large-scale-structure cosmology, dark matter or neutrino astroparticle physics, or particle-physics constraints that genuinely depend on cosmological evidence.

Manuscripts where the cosmology / astroparticle angle is decorative get redirected: pure-astrophysics to ApJ / MNRAS / A&A / AJ / PASA / PASJ; pure-particle-physics to PRD / JHEP / PRL / Nuclear Physics B / Physics Letters B / European Physical Journal C; pure-instrumentation to specialty venues (NIM-A, Astroparticle Physics, Experimental Astronomy); pure-mathematical-relativity to Classical and Quantum Gravity / GRG / Physical Review D.

The fix is to identify the cosmology or astroparticle question the work advances explicitly (which dark-matter / dark-energy / inflation / baryogenesis / neutrino-mass / modified-gravity / cosmic-ray-origin question), name it in the first abstract sentence, and either reframe around the cosmology / astroparticle stake or route to the appropriate specialty venue.

Check whether your JCAP manuscript has a load-bearing cosmology or astroparticle question →

Methodology below the JCAP bar

We frequently see JCAP manuscripts submit work with methodologies that meet a general physics-journal bar but fall short of JCAP's cosmology / astroparticle-community top-tier rigor.

JCAP referees (drawn from the active cosmology / astroparticle research community) specifically check whether the manuscript uses:

• appropriate statistical inference (Bayesian with explicit prior justification + posterior with convergence diagnostics R-hat and effective sample size + nested sampling for evidence calculation where model comparison matters, OR frequentist with explicit test statistic + p-value with proper treatment of look-elsewhere effect + confidence intervals via Feldman-Cousins where bounds are near physical limits)

• appropriate systematics treatment (named systematic uncertainties with quantitative budget, marginalization or profiling over nuisance parameters, sensitivity to assumed cosmology / dark-matter model / nuisance prior, cross-checks with alternative analysis pipelines)

• appropriate likelihood (Boltzmann codes named: CAMB / CLASS / hi_class / EFTCAMB

• sampling codes: MontePython / Cobaya / cosmosis / emcee / dynesty / PolyChord

• with version numbers)

• appropriate data treatment (Planck PR4 / ACT DR6 / SPT-3G / DES Y6 / DESI Y1 / Euclid Q1 / LSST Y1 / KiDS-1000 / HSC Y3 / BOSS / eBOSS / 6dFGS / WiggleZ named datasets with public-availability checks

• for high-energy cosmic-ray / neutrino work: IceCube point-source catalog / Pierre Auger UHECR catalog / HAWC / LHAASO / KM3NeT with named data releases)

• appropriate comparison to literature constraints (named recent results from the same dataset with comparable model, fair comparison of methodology)

Manuscripts with thin statistical rigor, missing systematics budget, undocumented likelihood codes, undefined data treatment, or no comparison to recent constraints face revision-or-reject decisions.

The fix is to use community-standard tools with version numbers, document every systematic uncertainty with quantitative budget, run nuisance-parameter marginalization or profiling, cross-check with alternative pipelines, compare to recent constraints from the same dataset, and report posterior convergence diagnostics or frequentist look-elsewhere corrections explicitly.

Check whether your JCAP methods package is reviewer-ready →

Package does not match JCAP flow

The third recurring pattern in JCAP-targeted manuscripts is preparation gaps that the SISSA/IOP arXiv-first editorial flow specifically penalizes.

JCAP editorial workflow expects:

• an arXiv posting made before you submit (JCAP requires an arXiv article id at submission, and the submitted version must be the same as the arXiv version)

• arXiv submission to the appropriate primary category (astro-ph.CO for cosmology, astro-ph.HE for high-energy astrophysics, hep-ph for particle phenomenology with cosmology cross-listing, hep-th for theoretical cosmology with hep-th cross-listing, gr-qc for gravitational-wave cosmology, astro-ph.IM for instrumentation) with appropriate cross-listings to ensure visibility across the relevant communities

• precise and specific author keywords drawn from the JCAP keyword list (vague keywords like "cosmology" or "dark matter" without sub-classification create routing friction, because the software picks the editor from your keywords and they cannot be changed after submission)

• proper handling of the preprint version (the submitted version must be the same as the arXiv version; once submitted, an article should not be replaced, and a substantially different new version means withdrawing and resubmitting)

• compliance with the SISSA-IOP joint publishing economics (subscription publication carries no author charge

• gold OA article publication charge of $3,455 (or £2,185 or €2,500), excluding VAT, per IOP Publishing's publication-charges page read on 2026-10-10, with IOP transformative agreements covering the charge for eligible authors at some institutions)

• a note to the editor explaining why JCAP is the venue (not PRD which is broader physics, not ApJ which is observational astronomy, not MNRAS which is broader astrophysics, not JHEP which is theoretical particle physics, not A&A which is broader astronomy and astrophysics), sent through the "write to editor" button on the preprint page because JCAP asks you not to include cover letters in the submission archive

Manuscripts that arrive without arXiv parallel posting, with mismatched keywords, or without JCAP-specific framing for the editor face desk-screen friction.

The fix is to post to arXiv before you submit to JCAP with correct primary and cross-listed categories, use specific cosmology / astroparticle keywords from the JCAP list, check institutional OA-agreement eligibility before submission, and explain to the editor why JCAP specifically over PRD / ApJ / MNRAS / JHEP / A&A.

Check whether your JCAP manuscript is submission-ready →

• Is JCAP a good journal?

• Physical Review D Submission Guide

• Rejected from JCAP? Where to submit next, for routing a cosmology paper after a scope or post-review rejection

• Astrophysical Journal Submission Guide

Submission caps: JCAP is published jointly by SISSA Medialab and IOP Publishing and publishes no word or figure limit. Its editorial policy says length should be appropriate to the information presented and that JCAP papers do not normally exceed 50 pages. JCAP requires an arXiv identifier at submission (arXiv-first policy), and manuscripts must be prepared in TeX/LaTeX, preferably with the JCAP template on Overleaf or the JCAP style class; other styles are accepted but are processed more slowly after acceptance.

The jcap.sissa.it/jcap submission portal checks the arXiv id and compiles the LaTeX on upload; tables and figures should be referred to in the text and always have a caption.

Last verified: 2026-10-10 against JCAP editorial pages, SISSA pages, and IOP publishing support.