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Welcome to the High Energy Network

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daveh
daveh's picture
Welcome to the High Energy Network

Welcome to the AAVSO International High Energy Network Forum and the High Energy Network Observing Section. The AAVSO International High Energy Network is dedicated to the optical monitoring of high energy astrophysical phenomena in the universe. It is an expansion of the AAVSO International Gamma-Ray Burst Network which had great success in discovering and observing the optical afterglows of gamma-ray bursts (GRBs). Observers around the world are able to respond in seconds or minutes to burst alerts sent by satellite, and are able to catch these rapidly evolving phenomena as quickly (if not more so) than professional observatories. The AAVSO still distributes GCN Notices and GCN Circulars, but the work of the High Energy Network has been largely done by a small group of observers on an informal basis as opportunities for new observations and targets arise. The High Energy Network Observing Section will now be a fully functioning AAVSO observing section on par with all of the other observing sections. AAVSO observers and researchers pursuing high energy sources can go beyond gamma-ray burst follow-ups to include observations of other astrophysical sources bright in gamma- and X-rays. These include Blazars and other Active Galactic Nuclei, and Galactic gamma-ray sources like flare stars and X-ray binaries. In addition, new high energy astrophysical phenomena including Gravitational Waves and Multi-messenger sources will be part of the High Energy Network. Both of these phenomena will require optical follow up to the main triggering event. As such, this provides AAVSO observers a unique opportunity to contribute to these new areas of research. The AAVSO International High Energy Network is a truly international endeavor, with observers from around the world actively conducting follow-ups and participating in High Energy Network campaigns. We invite researchers of high-energy phenomena to collaborate with AAVSO observers via Observing Campaigns on their sources of interest. It will also be the goal of the High Energy Network to work with institutions around the world that pursue high energy research. The High Energy Network webpage is currently in the process of being significantly updated and expanded. It will include significant technical depth and detailed information, numerous clickable links for drilling down to specific topics, and tools that can be used for research and observations. A new feature will be a High Energy Network News page which will attempt to continuously provide the latest information about high energy astrophysical objects and research. Additionally, a greatly expanded High Energy Target (HET) tool will be included to list all of the high energy objects in the VSX database. All ideas are welcome to further improve the High Energy Network, including new projects, collaboration with universities and research organizations, and additional high energy objects for observation.

Ccolvin968
Ccolvin968's picture
Hi Dave!

Hi Dave!

Sounds like a party! :)

What is the barrier of getting into reporting and observing HET's?

Will it be as simple as a DSLR or online tools?

Or would new gear and instruments need to be purchased?

Thanks!

Bikeman
Bikeman's picture
Public GW event alerts.

Excellent! As described in the introduction by Dave, Gravitational Wave (GW) events also call for follow-up searches at optical wavelengths.

The only optical counterpart observed so far for a GW event was AT2017gfo (for the  GW170817 merger of two neutron stars). Note that AT 2017gfo would have been perfectly well reachable by ambitious amateurs at around 18mag (if there had been public alerts at that time already...), as it was relatively close (40 Mpc). With a bit of luck we might see another such event, but unfortunately, this window of opportunity will close at the end of April 2020 when the major GW observatories will be turned off again. After improvements, they will go online again only in (probably) January 2022 (!), so anyone who wants to join the hunt for optical GW counterparts needs to act fast.

People who are hunting for optical GRB afterglows will feel quite "at home" as low-lateny GW alerts are also published via the GCN infrastructure. Others might find the learning curve a bit steeper, I recommend this as a starting point:

https://emfollow.docs.ligo.org/userguide/index.html

An existing professional collaboration that will accept follow-up images taken by amateurs is GRANDMA, see https://grandma-kilonovacatcher.lal.in2p3.fr/

Unfortunately this project never quite lived up to the promise of an automated workflow to submit amateur contributions, interested people should still get in touch with kilonovacatcher by GRANDMA to be able to submit images in a more manual fashion. 

Cheers

HB

daveh
daveh's picture
Welcome to the High Energy Network

Hello gents,

Thanks for your interest in the High Energy Network! Let me see if I can answer both of you in a single reply.

Regarding the barrier to entry, it's no different than any other AAVSO group. It's really a matter of what you prefer to use for observations. Personally I prefer the iTelescope network, but it's your choice. You would report in the same way as any observation you would make via VPhot. You mention other instruments. It occurred to me after I posted the greeting that there might be a place for the AAVSO spectroscopy folks since spectral characterization may be important.

To answer the second question, you're right when you say that the GRB observers  will be quite comfortable doing followup on GWs. Your reference to GRANDMA is interesting since I included that in the new HEN webpage. That is still under development but will have multiple links concerning GWs. I'll include the ligo link you sent on the page.

One of the things I think we might want to include at some point is a realtime notification of various high energy events such as GRBs and GWs possibly with a text message to your cell phone. I believe NASA Goddard Space Flight Center (they issue the GCNs) have something like that but I don't know the details.

So stay tuned...lots of interesting work ahead.

Dave

Bikeman
Bikeman's picture
As for the GW events, their

As for the GW events, their preferred alert mechanism is via XML VOevents, not via email or cellphone text.

So people who are interested in GW events have computers running 24/7 that connect to the GCN server and continuously listen for new evnets. That's not very well suited for the average amateur observer, tho.

The GW alerts are a bit special in the sense that for events that have a reasonable chance to have a EM bright counterpart , we are talking about distances of perhaps < 100 Mpc. At this distance, we still have rather complete catalogues for galaxies. The GW detectors will probably not be able to locate the event in the sky to better than 10s, but perhaps even 100s of deg^2. So the best strategy to catch a rapidly dimming counterpart will be to generate a list of galaxies that are consistent with the alert messages and provide these galaxies as targets, instead of everyone tiling the sky with rather random telescope pointings.

So it would be this list of candidate host galaxies that would need to be spread rapidly among amateurs, but this is not something that is delivered by the GW detector collaboration. The GRANDMA amateur collaboration will distribute a candidate galaxy list "internally" (email & web collaboration tool), but that is not rocket science and even if you cannot get GRANDMA to share their list via AAVSO websites, you could rather easily generate a list yourself. People can already "subscribe" to webpages here and be alerted by email when content is added (I'm not sure tho what the latency is).

Cheers

HB

daveh
daveh's picture
As for the GW events, their

OK...very cool! I sense there is a HEN project here as I indicated in my original post. You say there is a list of galaxies that would be better candidates, so lets start with that and work thru the details. Much better to have a focused objective rather than a shotgun approach. So lets start with this and keep it for the time being, if I understand correctly, within AAVSO. Can you come up with the list of galaxies?

Bikeman
Bikeman's picture
I have a little Raspberry PI

I have a little Raspberry PI at home that listens to GCN and will generate a first approximation of a galaxy target list (not too sophisticated but better than nothing) within about 2 or 3  minutes or so after an event alert. The thingy will then notify me via text &  email (and at night will actually switch my bedroom lights on (so my cats wake up and then they will wake me up :-) ).

Dave, if you send me an email address, I can have that process send you a copy automatically.

Cheers

HB

 

daveh
daveh's picture
Is Rasberry Pi something that

Is Rasberry Pi something that AAVSO members could access, in other words could it become an active part of the HEN website?

I contacted you on the AAVSO member's page with my email.

Dave

SFS
Raspberry Pi is a single

Raspberry Pi is a single board computer,very popular with hobbysts.  Personally, I perfer to use a microcontroler, because one can build even smaller systems with them.  For more information go to

https://www.raspberrypi.org/

daveh
daveh's picture
Welcome to the High Energy Network

Thanks for the info on Raspberry Pi. I guess what I was wondering about above is if there was a way to alert in real time HEN observers maybe thru the website. Something like a text to your cell phone. I know that NASA Goddard Space Flight Center has that sort of capability and I was wondering if HEN might be able to come up with a similar thing. Right now we have the GCN Circular and the LIGO/VIRGO Public Alert on the HEN Miscellaneous Links page. That's probably good enough for now, but it would be an interesting project to develop a real time capability.

Bikeman
Bikeman's picture
If the AAVSO would have a GCN

If the AAVSO would have a GCN notices VOevent listener (which can be something as simple as a  tiny python script, see this example code for GW public alerts https://emfollow.docs.ligo.org/userguide/tutorial/index.html ) it could then trigger actions from HQ that would notify interested AAVSO observers/HEN members. A possible solution would be that the VO events would automatically generate some content in the AAVSO website (here) for which users can subscribe, so they would get emails sent by the AAVSO content manangement system server.

You may also want to subscribe directly with GCN to get emails forwarding new GCN circulars to you , but Circulars are intended to be human readable, while the GCN notices are machine readable. For those new to GCN, see details here : https://gcn.gsfc.nasa.gov/ 

More ambitious AAVSO observers would probably run their own GCN listeners on their own hardware for even faster and perhaps semi-automatic responses.
That's what my Raspberry PI is doing. It's sitting next to the TV set, listens for alerts with a little python script derived from the example code mentioned above, and beeps, blinks, displays a summary on an LCD and sends messages out when something interesting happens (where "interesting" is a set of my very own criteria, based on the equipment I have access to). It's kind of customized for me and the specific hardware attached to it and is only made for GW alerts (that will end in less than two months), so it won't make much sense to share this solution as it would need some work to be useful in a more general context, say for GRB afterglow hunting. But the link posted above is a good starting point for anyone who wants to have real-time access to GCN notices.

Cheers

HB

Bikeman
Bikeman's picture
LIGO + VIRGO GW detectors end science run

 
News from LIGO and Virgo, published on the openlvem mailing list:

Hi All:

In response to the COVID-19 pandemic, LIGO and Virgo observation mode operation will end on Friday Mar 27th at 17:00 UTC (12 pm Central time, 10 am Pacific, 6 pm Central European time). It is unknown at this time when observing mode operation may resume. We will continue to provide updates on this list, at www.ligo.org, at www.virgo-gw.eu, and at treasuremap.space/status as the circumstances change. We think this will minimize risk to observatory staff, to the public and to our science in these trying times.

There will be a LIGO-Virgo observer call on 2 April 2020 at which we can discuss this further if people would like more information.

Stay safe,
Patrick and Jo for the LIGO-Virgo Collaboration

--

daveh
daveh's picture
Possible activity in Blazar S5 1803+78

We have information from observers in Spain that it may be likely that this object is undergoing an explosion. The last observation in the AAVSO database was last night by observer LDJ at mag 14.3. The previous measurement was 15.82 on 4/4/2020. The optical observations are in agreement with gamma ray data from NASA. Please observe Blazar S5 1803+78. Thanks.

Dave (HDHA)

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