Rafael C. Nunes
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Research Interests
Rafael C. Nunes has a total of 104 co-authors. Here are the top co-authors by number of shared publications:
- Suresh Kumar
Plaksha University
34 shared publications - Eleonora Di Valentino
University of Sheffield
29 shared publications - Supriya Pan
Presidency University
16 shared publications - Ozgur Akarsu
Istanbul Technical University
14 shared publications - José Carlos Neves de Araujo
Instituto Nacional de Pesquisas Espaciais
13 shared publications - Armando Bernui
Observatório Nacional
12 shared publications
Latest Publications
- 1 October 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 114 (8)
Constraining cosmological and astrophysical parameters with the cosmic star formation history
- 1 October 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 114 (8)
Constraining cosmological and astrophysical parameters with the cosmic star formation history
- 29 September 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 114 (6)
Modeling uncertainties in modified gravity predictions for the stochastic gravitational-wave background
- 29 September 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 114 (6)
Modeling uncertainties in modified gravity predictions for the stochastic gravitational-wave background
- 10 August 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 114 (4) , 043511
Are cosmological data excluding sterile neutrinos or only the fully thermalized limit?
We present a cosmological reassessment of light sterile-neutrino scenarios, examining whether current observations exclude sterile neutrinos as a class or primarily constrain the fully thermalized case. We consider three distinct realizations; (i) a fully thermalized sterile (FTS) species, (ii) a different-temperature sterile-neutrino thermal relic (DTS) relative to the active neutrino background and (iii) a Dodelson-Widrow-like (DW) sterile neutrino with reduced phase-space normalization. Constraints are derived within both $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ and the CPL dynamical dark-energy framework using combinations of Planck-Cosmic Microwave Background data, DESI DR2 BAO measurements, and the PantheonPlus and Union3 Type Ia supernova samples. For baseline data combinations without a local ${H}_{0}$ prior, the FTS scenario is strongly disfavored in both cosmological models. Adding the local ${H}_{0}^{\mathrm{DN}}$ prior allows $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}+\mathrm{FTS}$ to accommodate the high local ${H}_{0}$ value and become statistically competitive with standard $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ once SNIa data are included, although the sterile-neutrino mass remains consistent with zero. By contrast, partially populated sterile-neutrino scenarios remain viable: the DW realization is broadly compatible with current observations, while the DTS scenario yields the least cosmological pressure among the cases considered. Overall, cosmological data mainly require a strongly suppressed effective sterile abundance, leading to tight constraints on ${m}_{s}^{\mathrm{eff}}$ while allowing substantially weaker bounds on the physical sterile mass. We conclude that current observations do not generically exclude sterile neutrinos, but rather place strong pressure on fully thermalized or highly populated scenarios, highlighting the importance of production history and phase-space distribution when interpreting cosmological constraints.- 10 August 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 114 (4) , 043511
Are cosmological data excluding sterile neutrinos or only the fully thermalized limit?
We present a cosmological reassessment of light sterile-neutrino scenarios, examining whether current observations exclude sterile neutrinos as a class or primarily constrain the fully thermalized case. We consider three distinct realizations; (i) a fully thermalized sterile (FTS) species, (ii) a different-temperature sterile-neutrino thermal relic (DTS) relative to the active neutrino background and (iii) a Dodelson-Widrow-like (DW) sterile neutrino with reduced phase-space normalization. Constraints are derived within both $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ and the CPL dynamical dark-energy framework using combinations of Planck-Cosmic Microwave Background data, DESI DR2 BAO measurements, and the PantheonPlus and Union3 Type Ia supernova samples. For baseline data combinations without a local ${H}_{0}$ prior, the FTS scenario is strongly disfavored in both cosmological models. Adding the local ${H}_{0}^{\mathrm{DN}}$ prior allows $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}+\mathrm{FTS}$ to accommodate the high local ${H}_{0}$ value and become statistically competitive with standard $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ once SNIa data are included, although the sterile-neutrino mass remains consistent with zero. By contrast, partially populated sterile-neutrino scenarios remain viable: the DW realization is broadly compatible with current observations, while the DTS scenario yields the least cosmological pressure among the cases considered. Overall, cosmological data mainly require a strongly suppressed effective sterile abundance, leading to tight constraints on ${m}_{s}^{\mathrm{eff}}$ while allowing substantially weaker bounds on the physical sterile mass. We conclude that current observations do not generically exclude sterile neutrinos, but rather place strong pressure on fully thermalized or highly populated scenarios, highlighting the importance of production history and phase-space distribution when interpreting cosmological constraints.- Open Access
- 30 July 2026
- Published by Universidade Federal do Espirito Santo in Cadernos de Astronomia
- Vol. 7 (Especial) , 72-76
Escala acústica bariônica em z_eff = 0,166 com galáxias azuis do SDSS
Trabalho apresentado no evento As Astrocientistas: III Encontro Brasiliero de Meninas e Mulheres da Astrofísica, Cosmologia e Gravitação, realizado entre os dias 31 de março e 4 de abril de 2025.
- 30 July 2026
- Published by Universidade Federal do Espirito Santo in Cadernos de Astronomia
- Vol. 7 (Especial) , 72-76
Open AccessEscala acústica bariônica em z_eff = 0,166 com galáxias azuis do SDSS
Trabalho apresentado no evento As Astrocientistas: III Encontro Brasiliero de Meninas e Mulheres da Astrofísica, Cosmologia e Gravitação, realizado entre os dias 31 de março e 4 de abril de 2025.
- 29 July 2026
- Published by Elsevier in Physics of the Dark Universe
- Vol. 53
Testing scale-dependent suppression of structure growth in the linear regime
- 29 July 2026
- Published by Elsevier in Physics of the Dark Universe
- Vol. 53
Testing scale-dependent suppression of structure growth in the linear regime
- Open Access
- 5 June 2026
- Published by Elsevier in SSRN Electronic Journal
Tracing the Evolution of $\Omega_m(z)$ over the Last 10 Billion Years with Non-parametric MethodsWe investigate the redshift evolution of the matter density parameter, $\Omega_m(z)$, using galaxy cluster gas mass fraction measurements combined with cosmic chronometer $H(z)$ data and type Ia supernova luminosity distances. Beyond reconstructing the late-time expansion history, our analysis probes the normalization of the cosmological matter sector, which plays a central role in current tensions involving weak lensing measurements, cluster abundance analyses, and the $S_8$ parameter. Our approach employs Gaussian Process Regression to reconstruct $\Omega_m(z)$ in a non-parametric way, remaining only weakly dependent on a specific background cosmology. The reconstructed evolution is consistent with the standard $\rho_m \propto (1+z)^3$ scaling predicted by the $\Lambda$CDM model. We obtain $\Omega_{m0}=0.296 \pm 0.044$ from the 44-cluster sample, and $\Omega_{m0}=0.271 \pm 0.016$, $0.253 \pm 0.017$, and $0.210 \pm 0.013$ for the 103-cluster compilation, depending on the adopted mass calibration. While the reconstructed $\Omega_m(z)$ evolution remains robust and consistent with the expected $\Lambda$CDM behaviour, the inferred normalization of $\Omega_{m0}$ exhibits a strong dependence on cluster mass calibration. Within this framework, mass bias emerges as the dominant source of uncertainty, exceeding statistical errors and directly impacting the cosmological matter normalization inferred from cluster observations.- 5 June 2026
- Published by Elsevier in SSRN Electronic Journal
Open AccessTracing the Evolution of $\Omega_m(z)$ over the Last 10 Billion Years with Non-parametric MethodsWe investigate the redshift evolution of the matter density parameter, $\Omega_m(z)$, using galaxy cluster gas mass fraction measurements combined with cosmic chronometer $H(z)$ data and type Ia supernova luminosity distances. Beyond reconstructing the late-time expansion history, our analysis probes the normalization of the cosmological matter sector, which plays a central role in current tensions involving weak lensing measurements, cluster abundance analyses, and the $S_8$ parameter. Our approach employs Gaussian Process Regression to reconstruct $\Omega_m(z)$ in a non-parametric way, remaining only weakly dependent on a specific background cosmology. The reconstructed evolution is consistent with the standard $\rho_m \propto (1+z)^3$ scaling predicted by the $\Lambda$CDM model. We obtain $\Omega_{m0}=0.296 \pm 0.044$ from the 44-cluster sample, and $\Omega_{m0}=0.271 \pm 0.016$, $0.253 \pm 0.017$, and $0.210 \pm 0.013$ for the 103-cluster compilation, depending on the adopted mass calibration. While the reconstructed $\Omega_m(z)$ evolution remains robust and consistent with the expected $\Lambda$CDM behaviour, the inferred normalization of $\Omega_{m0}$ exhibits a strong dependence on cluster mass calibration. Within this framework, mass bias emerges as the dominant source of uncertainty, exceeding statistical errors and directly impacting the cosmological matter normalization inferred from cluster observations. - Open Access
- 29 May 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 113 (10)
Updated constraints on omnipotent dark energy: A comprehensive analysis with CMB and BAO data
In this work, we present updated observational constraints on the parameter space of the DMS20 dark-energy model, a member of the (ODE) class. Our analysis combines multiple cosmic microwave background datasets—including measurements from the Planck satellite (PL18), the South Pole Telescope (SPT), and the Wilkinson Microwave Anisotropy Probe (WMAP)—with Type Ia supernova data from the Pantheon + catalog (PP), and baryon acoustic oscillation measurements from the Dark Energy Spectroscopic Instrument and Sloan Digital Sky Survey. We find that certain data combinations, such as SPT + WMAP + BAO and P L 18 + BAO , can reduce the significance of the H 0 tension below 1 σ , but with considerably large uncertainties. However, the inclusion of PP data restores the tension in H 0 . To provide a comprehensive view of the ODE phenomenology, we also investigate the evolution of its energy density, emphasizing its dynamical behavior at low redshifts. Our results generically exhibit multiple phantom divide line crossings in a single expansion history; if confirmed, this points beyond the simplest minimally coupled canonical single-field quintessence/phantom descriptions and motivates more general dark-sector realizations.
- 29 May 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 113 (10)
Open AccessUpdated constraints on omnipotent dark energy: A comprehensive analysis with CMB and BAO data
In this work, we present updated observational constraints on the parameter space of the DMS20 dark-energy model, a member of the (ODE) class. Our analysis combines multiple cosmic microwave background datasets—including measurements from the Planck satellite (PL18), the South Pole Telescope (SPT), and the Wilkinson Microwave Anisotropy Probe (WMAP)—with Type Ia supernova data from the Pantheon + catalog (PP), and baryon acoustic oscillation measurements from the Dark Energy Spectroscopic Instrument and Sloan Digital Sky Survey. We find that certain data combinations, such as SPT + WMAP + BAO and P L 18 + BAO , can reduce the significance of the H 0 tension below 1 σ , but with considerably large uncertainties. However, the inclusion of PP data restores the tension in H 0 . To provide a comprehensive view of the ODE phenomenology, we also investigate the evolution of its energy density, emphasizing its dynamical behavior at low redshifts. Our results generically exhibit multiple phantom divide line crossings in a single expansion history; if confirmed, this points beyond the simplest minimally coupled canonical single-field quintessence/phantom descriptions and motivates more general dark-sector realizations.
- Open Access
- 9 April 2026
- Published by Universidade Federal do Espirito Santo in Cadernos de Astronomia
- Vol. 7 (1) , 6-24
Tensões cosmológicas em H0 e S8: panorama atual
O modelo cosmológico padrão tem fornecido, por várias décadas, a descrição consistente de uma ampla gama de observações cosmológicas e astrofísicas. Apesar desse sucesso, discrepâncias persistentes na determinação de parâmetros fundamentais, em particular a constante de Hubble (H0) e a amplitude do crescimento das estruturas, frequentemente parametrizada por S8, revelam tensões significativas entre sondas do universo primordial e tardio, com diferentes níveis de significância estatística. Essas tensões podem estar parcialmente associadas a incertezas sistemáticas ainda não completamente compreendidas, mas também motivam a investigação de extensões do ΛCDM, incluindo modificações na energia escura, no setor escuro e na gravidade em grandes escalas. Neste trabalho de revisão didática, apresentamos uma visão geral das principais observações atualmente envolvidas nessas discrepâncias, discutimos seus potenciais vieses observacionais e sintetizamos os cenários mais relevantes, destacando as perspectivas oferecidas pelos levantamentos cosmológicos da geração atual.
- 9 April 2026
- Published by Universidade Federal do Espirito Santo in Cadernos de Astronomia
- Vol. 7 (1) , 6-24
Open AccessTensões cosmológicas em H0 e S8: panorama atual
O modelo cosmológico padrão tem fornecido, por várias décadas, a descrição consistente de uma ampla gama de observações cosmológicas e astrofísicas. Apesar desse sucesso, discrepâncias persistentes na determinação de parâmetros fundamentais, em particular a constante de Hubble (H0) e a amplitude do crescimento das estruturas, frequentemente parametrizada por S8, revelam tensões significativas entre sondas do universo primordial e tardio, com diferentes níveis de significância estatística. Essas tensões podem estar parcialmente associadas a incertezas sistemáticas ainda não completamente compreendidas, mas também motivam a investigação de extensões do ΛCDM, incluindo modificações na energia escura, no setor escuro e na gravidade em grandes escalas. Neste trabalho de revisão didática, apresentamos uma visão geral das principais observações atualmente envolvidas nessas discrepâncias, discutimos seus potenciais vieses observacionais e sintetizamos os cenários mais relevantes, destacando as perspectivas oferecidas pelos levantamentos cosmológicos da geração atual.
- 1 April 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 113 (8)
Joint constraints on neutrinos and dynamical dark energy in minimally modified gravity
- 1 April 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 113 (8)
Joint constraints on neutrinos and dynamical dark energy in minimally modified gravity
- 18 March 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 113 (6)
One-loop power spectrum corrections in interacting dark energy cosmologies
- 18 March 2026
- Published by American Physical Society (APS) in Physical Review D
- Vol. 113 (6)
One-loop power spectrum corrections in interacting dark energy cosmologies