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The Supernova Remnant G11.2-0.3 and its central Pulsar
The plerion inside the composite Supernova Remnant G11.2-0.3 appears to be
dominated by the magnetic field to an extent unprecedented among well known
cases. We discuss its evolution as determined by a central pulsar and the
interaction with the surrounding thermal remnant, which in turn interacts with
the ambient medium. We find that a plausible scenario exists, where all the
observations can be reproduced with rather typical values for the parameters of
the system; we also obtain the most likely period for the still undetected
pulsar.Comment: 10 pages, to be published on ApJ Letters. Formatted using AASTe
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A model for the radiations from the compact strong sources
Model for origins and time variations of radiation spectrum over all wave band
A Scalable Telemetry Framework for Zero Touch Optical Network Management
The interest about Zero Touch Network and Service Management (ZSM) is rapidly emerging. As defined by ETSI, the ZSM architecture is based on a closed-loop/feedback control of the network and the services. Such closed-loop control can be based on the Boyd's Observe Orient Decide and Act (OODA) loop that matches some specific management functions such as Data Collection, Data Analytics, Intelligence, Orchestration and Control. An efficient implementation of such control loop allows the network to timely adapt to changes and maintain the required quality of service.Many solutions for collecting network parameters (i.e., implementing ZSM data collection) are proposed that fall under the broad umbrella of network telemetry. An example is the Google gRPC, that represented one of the first solutions to provide a framework for data collection. Since then, the number of available frameworks is proliferating. In this paper we propose the utilisation of Apache Kafka as a framework for collecting optical network parameters. Then, the paper goes beyond that by proposing and showing how Apache Kafka can be effective for supporting data exchange and management of whole ZSM closed-loop.Experimental evaluation results show that, even when a large number of data are collected, the solution is scalable and the time to disseminate the parameter values is short. Indeed, the difference between the reception time and the generation time of data is, on average, 40-50ms when about four thousand messages are generated
Precursor Plerionic Activity and High Energy Gamma-Ray Emission in the Supranova Model of Gamma-Ray Bursts
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 afterglows. A crucial
ingredient of this model yet to be studied is the fast-rotating pulsar that
should be active during the time interval between the SN and the GRB, driving a
powerful wind and a luminous plerionic nebula. We discuss some observational
consequences of this precursor plerion, which should provide important tests
for the supranova model: 1) the fragmentation of the outlying SN ejecta
material by the plerion and its implications for Fe line emission; and 2) the
effect of inverse Compton cooling and emission in the GRB external shock due to
the plerion radiation field. The plerion-induced inverse Compton emission can
dominate in the GeV-TeV energy range during the afterglow, being detectable by
GLAST from redshifts and distinguishable from self-Compton
emission by its spectrum and light curve. The prospects for direct detection
and identification of the precursor plerion emission are also briefly
considered.Comment: ApJ vol.583, in pres
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