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Daniele Fargion

Publications and source records attributed to Daniele Fargion.

57 records · Page 4Linked to original sources

Slowing Down and Speeding Up PSR's Periods: A Shapiro Telescope tracing Dark Matter

Dark matter influence globally galactic Keplerian motions and individually, by microlensing, star's acromatic luminosities. Moreover gravity slows down time as probed by gravitational redshift. Therefore pulsar's (PSR's) periods may record, by slowing and speeding up, any Dark MACHO crossing along the line-of-sight. This phase delay, a Shapiro Phase Delay, is a gravitational integral one and has been probed since 1964 on planets by radar echoes. We discovered in PSRs catalog a few rare PSRs (with negative period derivatives) consistent with speeding up by Shapiro delay due to MACHOs. We propose to rediscover the Shapiro effect on our solar system (for Jupiter, Mars, Sun) to calibrate a new "Shapiro Telescope Array" made by collective monitoring of the sample of PSRs along the ecliptic plane.

astro-ph↗

GRBs and SGRs as precessing gamma jets

The GRB980425-SN1998bw association put in severe strain and contradiction the simplest "candle" fireball model for GRBs. We probed that statistically the association is reliable, the energy luminosity and probability puzzles between cosmic and near by GRBs find a solution within a precessing gamma jet model either for GRBs and SGRs. The expected repetitivity for GRB 980425 has been already, probably, observed on GRB980712.

astro-ph↗

Tidal Effects of Passing Planets and Mass Extinctions

Recent observations suggest that many planetary-mass objects may be present in the outer solar system between the Kuiper belt and the Oort cloud. Gravitational perturbations may occasionally bring them into the inner solar system. Their passage near Earth could have generated gigantic tidal waves, large volcanic eruptions, sea regressions, large meteoritic impacts and drastic changes in global climate. They could have caused the major biological mass extinctions in the past 600 My as documented in the geological records.

astro-ph↗