High energy emission components in the short GRB 090510 (2009)
Corsi, Alessandra, Guetta, Dafne, Piro, Luigi
We investigate the origin of the prompt and delayed emission observed in the short GRB 090510. We first attempt to explain the soft-to-hard spectral evolution associated to the delayed onset of a GeV...
Is the Gamma Ray Bursts emission suppressed at high energy? (2009)
We compare the luminosity function and rate inferred from the GBM long bursts peak flux distribution with those inferred from the Swift and BATSE peak flux distribution. We find that the GBM, BATSE...
GeV emission from short Gamma-Ray Bursts: the case of GRB 081024B (2009)
Corsi, Alessandra, Guetta, Dafne, Piro, Luigi
We investigate the origin of the high energy tail detected by Fermi/LAT in the short GRB 081024B through synchrotron and self-Compton emission in either the internal or external shock models. In the...
Short Gamma-Ray Bursts and Gravitational Waves from Dynamically Formed Merging Binaries (2008)
Merging binary systems consisting of two collapsed objects are among the most promising sources of high frequency gravitational wave, GW, signals for ground based interferometers. Double neutron star...
A Universal Central Engine Hypothesis for Short and Long GRBs (2008)
Eichler, David, Guetta, Dafne, Manis, Hadar
It is noted that X-ray tails (XRTs) of short, hard $\gamma$-ray bursts (SHBs) are similar to X-ray flashes (XRFs). We suggest a universal central engine hypothesis, as a way of accounting for this...
Antonelli, L. Angelo, Testa, Vincenzo, Romano, Patrizia, Guetta, Dafne, Torii, Ken'ichi, D'Elia, Valerio, ...
Context. GRB050721 was detected by Swift and promptly followed-up, in the X-ray by Swift itself and, in the optical band, by the VLT operated, for the first time, in rapid response mode. A...
The variable X-ray light curve of GRB 050713A: the case of refreshed shocks (2007)
Guetta, Dafne, Fiore, Fabrizio, D'Elia, Valerio, Perna, R., Antonelli, L. Angelo, Piranomonte, Silvia, ...
We present a detailed study of the spectral and temporal properties of the X-ray and optical emission of GRB050713a up to 0.5 day after the main GRB event. The X-ray light curve exhibits large...
Do long-duration GRBs follow star formation? (2007)
We compare the luminosity function and rate inferred from the BATSE long bursts peak flux distribution with those inferred from the Swift peak flux distribution. We find that both the BATSE and the...
On the Rates of Gamma Ray Bursts and Type Ib/c Supernovae (2006)
Guetta, Dafne, Della Valle, Massimo
We measure the local rates of ``low-luminosity'' (LL-GRBs, i.e. L
Short GRBs: Rates and luminosity function implications (2006)
We compare the luminosity function and rate inferred from the BATSE short hard bursts (SHBs) peak flux distribution with the redshift and luminosity distributions of SHBs observed by Swift/HETE II....
Hopman, Clovis, Guetta, Dafne, Waxman, Eli, Zwart, Simon Portegies
Short-hard gamma-ray bursts (SHBs) may arise from gravitational wave (GW) driven mergers of double neutron star (DNS) systems. DNSs may be "primordial" or can form dynamically by binary exchange...
The rate and luminosity function of Short GRBs (2006)
We compare the luminosity function and rate inferred from the BATSE short hard bursts (SHBs) peak flux distribution with the redshift and luminosity distributions of SHBs observed by Swift/HETE II....
The BATSE-Swift luminosity and redshift distributions of short-duration GRBs (2005)
We compare the luminosity function and rate inferred from the BATSE short hard bursts (SHBs) peak flux distribution with the redshift and luminosity distributions of SHBs observed by Swift/HETE II....
Are all Gamma Ray Bursts like GRB 980425, GRB 030329 and GRB 031203? (2004)
Guetta, Dafne, Perna, Rosalba, Stella, Luigi, Vietri, Mario
We study the probability that three GRBs (980425, 030329, 031203) are found within z=0.17, given the luminosity functions consistent with the log N-log S relationship for classical cosmological...
The Luminosity and Redshift Distributions of Short-Duration GRB (2004)
Using the BATSE peak flux distribution we rederive the short GRBs luminosity function and compare it with the observed redshift distribution of long bursts. We show that both distributions are...
Constraining the Structure of GRB Jets Through the log(N)-log(S) Distribution (2004)
Guetta, Dafne, Granot, Jonathan, Begelman, Mitchell C.
A general formalism is developed for calculating the luminosity function and the expected number $N$ of observed GRBs above a peak photon flux $S$ for any GRB jet structure. This new formalism...
Internal shocks and the blazar sequence. Low and intermediate power BL Lac objects (2004)
Guetta, Dafne, Ghisellini, Gabriele, Lazzati, Davide, Celotti, Annalisa
We consider internal shocks as the main dissipation mechanism responsible for the emission in blazars and show that it can satisfactorily account for the properties of all blazars. In particular, we...
Internal shocks and the blazar sequence. Low and intermediate power BL Lac objects (2004)
Guetta, Dafne, Ghisellini, Gabriele, Lazzati, Davide, Celotti, Annalisa
We consider internal shocks as the main dissipation mechanism responsible for the emission in blazars and show that it can satisfactorily account for the properties of all blazars. In particular, we...
Ehud Nakar, Jonathan Granot, Dafne Guetta
The two leading models for the structure of gamma-ray burst (GRB) jets are the uniform jet model and the universal structured jet (USJ) model. In the latter, all GRB jets are intrinsically identical...
Testing the Predictions of the Universal Structured GRB Jet Model (2003)
Nakar, Ehud, Granot, Jonathan, Guetta, Dafne
The two leading models for the structure of GRB jets are the uniform jet model and the universal structured jet (USJ) model. In the latter, all GRB jets are intrinsically identical and the energy per...
Explaining the High Energy Spectral Component in GRB 941017 (2003)
Granot, Jonathan, Guetta, Dafne
The gamma-ray burst (GRB) of October 17, 1994 (941017), showed a distinct high energy spectral component extending from $\lesssim$ a few MeV to $\gtrsim$ 200 MeV, in addition to the typical GRB...
Gamma Ray Bursts in Pulsar Wind Bubbles: Observational implications (2003)
Guetta, Dafne, Granot, Jonathan
We present the main observational features expected for Gamma-Ray Bursts (GRBs) that occur inside pulsar wind bubbles (PWBs). This is the most natural outcome of the supranova model, where initially...
On the generation of UHECRs in GRBs: a reappraisal (2003)
Vietri, Mario, De Marco, Daniel, Guetta, Dafne
We re-examine critically the arguments raised against the theory that Ultra High Energy Cosmic Rays observed at Earth are produced in Gamma Ray Bursts. These include the limitations to the highest...
Inoue, Susumu, Guetta, Dafne, Pacini, Franco
The supranova model of gamma-ray bursts ( GRBs), in which the GRB event is preceded by a supernova (SN) explosion by a few months to years, has recently gained support from Fe line detections in the...
Neutrinos from Gamma-Ray Bursts in Pulsar Wind Bubbles: \sim 10^{16} eV (2002)
Guetta, Dafne, Granot, Jonathan
The supranova model for Gamma-Ray Bursts (GRBs) is becoming increasingly more popular. In this scenario the GRB occurs weeks to years after a supernova explosion, and is located inside a pulsar wind...
Neutrinos from Pulsar Wind Bubbles as Precursors to Gamma-Ray Bursts (2002)
Granot, Jonathan, Guetta, Dafne
The supranova model for gamma-ray bursts (GRBs) has recently gained popularity. In this scenario the GRB occurs weeks to years after a supernova explosion, and is located inside a pulsar wind bubble...
Gamma-Ray Bursts in Pulsar Wind Bubbles: Putting the Pieces Together (2002)
Granot, Jonathan, Guetta, Dafne
We present the main observational features expected for GRBs that occur inside pulsar wind bubbles (PWBs). This is the most natural outcome of supranova model where initially a supernova explosion...
High Energy Emission from the Prompt Gamma-Ray Burst (2002)
Guetta, Dafne, Granot, Jonathan
We study the synchrotron and synchrotron self-Compton (SSC) emission from internal shocks that are responsible for the prompt gamma-ray emission in GRBs, and consider the relation between these two...
Neutrino flux predictions for Galactic plerions (2002)
We consider a class of plerions that have been detected in the TeV range, and investigate the possibility that the emission is due to \pi^0 decay. From the TeV flux we derive what is the expected \nu...
Observational Implications of a Plerionic Environment for GRBs (2002)
Guetta, Dafne, Granot, Jonathan
We consider GRBs that occur inside pulsar wind bubbles (PWBs), in the context of the supranova model, where initially a supernova explosion takes place, leaving behind a supra-massive neutron star...
Gamma Ray Bursts from the First Stars: Neutrino Signals (2002)
Schneider, Raffaella, Guetta, Dafne, Ferrara, Andrea
If the first (PopIII) stars were very massive, their final fate is to collapse into very massive black holes. Once a proto-black hole has formed into the stellar core, accretion continues through a...
Inoue, Susumu, Guetta, Dafne, Pacini, Franco
The supranova model of gamma-ray bursts (GRBs), in which the GRB event is preceded by a supernova (SN) explosion by a few months to years, has recently gained support from Fe line detections in X-ray...
On the neutrino flux from Gamma Ray Bursts: an overview (2001)
Observations imply that gamma-ray bursts (GRBs) are produced by the dissipation of the kinetic energy of a highly relativistic fireball. Photo-meson interactions of protons with gamma-rays within the...
We describe a calculation of the two-photon decays of heavy vector-mesons, $B^*\to B\gamma\gamma$ and $D^*\to D\gamma\gamma$, by using the ``heavy meson chiral Lagrangian''. The decay amplitudes are...
$\omega-\rho$ Mixing and the $\omega\to\pi\pi\gamma$ Decay (2000)
We reexamine the $\omega \to \pi^{0} \pi^{0} \gamma $ decay, adding the effect of $\omega-\rho$ mixing to the amplitude calculated with the aid of chiral perturbation theory and vector meson...
We study the novel decays $B^{*}\to B\gamma\gamma $ and $D^{*}\to D\gamma \gamma $ using the framework of the Heavy Meson Chiral Lagrangian (HM$\chi$L) to leading order in chiral perturbation theory....
$B\to\tau\mu (X)$ decays in SUSY models without R-parity (1998)
Guetta, Dafne, Mira, Jesus M., Nardi, Enrico
Being strictly forbidden in the standard model, experimental detection of the lepton flavor violating decays $B(\bar B)\to\tau^+\mu^-$ and $b(\bar b)\to X\tau^+\mu^-$ would constitute an unmistakable...
Effects of R-parity Violating Couplings on CP Asymmetries in Neutral B Decays (1998)
A detailed analysis of the effects of supersymmetric models without R-parity on various CP asymmetries in neutral $B$ decays is given. We concentrate on models with Abelian horizontal symmetries that...
Searching for New Physics in Rare $B \to \tau$ Decays (1997)
The rare decays {$B^- \to \tau \bar\nu$}, \mbox{$B \to \tau^+ \tau^-$}, {$b \to X \nu \bar\nu$} and \mbox{$b \to X \tau^+ \tau^-$} all contain third generation leptons in the final state, and hence...