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New capability - slitless grating to ID new/transient objects

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archiving of spectra
Robin Leadbeater's picture
Robin Leadbeater
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Joined: 2012-10-08

Hi John,

This of course is a my personal view

I  dont need the AAVSAO to provide tools to manipulate spectra. They can be obtained elswhere.

I see little value in collecting data on a wide range of targets just for the sake of it and the idea that a database of thousands of spectra can be thrown to a groups of people with no expertise in the field and we should expect something useful to come out of it seems to me  absurd.

I prefer to work on targeted projects where the requirements are well defined and I know my data fulfil them. I am happy to work with and be steered by the professionals in the production and subsequent analysis of the data.   Pro-Am spectroscopy is growing rapidly without  AAVSO support and the amount of data collected during various campaigns is increasing significantly.  It is universally apreciated by the professionals involved who are apreciative of  (and it has to be said generally surprised by) the quality of data produced. AAVSO is therefore entering this area somewhat late and I feel that it is important that AAVSO builds on the progress that has been made rather than potentially degrade or undermine it, something that, reading  some of the posts here, I believe is a significant risk. 

My main concern is though that the data  collected to date is stored scattered around  websites which  may not be around in 5 years let alone 50.  A case in point is the epsilon Aurigae spectroscopic data. I took on the task of collating and storing amateur spectra during the campaign making sure as far as possible that the data were in a useful format. The resulting collection of spectra (880 spectra from 23 observers) is accessible here.

http://www.threehillsobservatory.co.uk/astro/epsaur_campaign/epsaur_campaign_spectra_table.htm

with the spectra either stored on my website or on websites linked  from it. This collection of spectra is  the largest on a single object produced by amateurs to date and has already generated several papers in JAAVSO and is the subject of study currently by  professional groups. Storage here was intended to be a temporary measure and while I hope to be around when the next eclipse comes around in 25 years, this is by no means guaranteed so a more permanent and secure home for this data would be useful.

 

Cheers

Robin

Spectroscopy Archives
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HPO
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Joined: 2010-07-23

 

Hi Ken,

As others have pointed out, spectra archiving is much harder than photometric archiving. I think the answer is to work with projects. Specific projects request spectra and that spectra is submitted, processed and analyzed. The data are then stored. Just what point of the processing should the data be stored? I think the answer may be the final analysed data and/or final calibrated line profile. Because the quality of spectra and processing can vary greatly, there would need to be much tighter control than for photometry. I think this should be handled within a given project. A project leader would be responsible for handling and qualifying the data. While important in photometry, quality if far more important than quantity for spectroscopy. 

As has been discussed before, I think the Star Analyser or Rainbow Optics spectrographs can be a good learning tool, but most projects will need higher resolution and that takes most people to a much higher level, both financially and equipment wise.

As I have said before, in addition to specific projects i think the AAVSO could play a very big role using low resolution spectrographs to get people interested and experienced with spectroscopy. I know several people who are very interested, but are having a hard time getting started. Mentor programs would be great as well as a possible user guide for those starting out. Spectroscopy can seem overwhelming, but just like photometry, once you get into it, it all makes sense and is not hard, but there is a learning curve. In the past perhaps the biggest hurtle was the software. Now with the RSpec processing software people have something that is not only easy and fun to use, but more importantly it encourages one to experiment without worrying about crashing or getting lost.

Jeff

This is a very good point.
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uis01
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This is a very good point.  It may work better to organize any universal archive around specific campaigns.  That could ensure integrity and standards that suit a specific purpose in a single set of data within the database.  Then the larger database is designed to bassically host and organize the different programs.  That would be a very different approach from the photometry database, but the AAVSO's experience and long-term web presence would still be a valuable contribution.

Arne, in an earlier message
Ken4optics's picture
Ken4optics
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Joined: 2012-04-02

Arne, in an earlier message indicates a significant investment in spectroscopy:

To quote:

- Star Analyzer 100. This is mounted on W28 and will be used for faint classification purposes.

- DSS-7. This will be placed on the Cohen/Menke 35cm; primarily for faint classification purposes.

- Optomechanics 10C spectrograph (long slit, like SGS). Morgan 61cm. general purpose

- echelle spectrograph to be built from ANS group. Hawkins Pond 80cm. general purpose.

- Eshell. TM61. radial velocity, bright stars

- Eshell. OC61. radial velocity, bright stars

All of these systems are either already at the telescope site or at HQ (except for the Hawkins Pond system). We expect them to all be operational during 2013.

If these projects come to fruition, there will be an enormous capablity sitting there.

Who will make use of this equipement? Who will select, manage and control the various projects? What will be the operational guidelines?

AAVSO Spectroscopy
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HPO
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Joined: 2010-07-23

 

Hi Ken,

You ask some most important questions. That is a signficant equipment investment and I wonder why? One thing the AAVSO must be careful of and that is spectroscopy has been the domain of big telescope observatories. The AAVSO is doomed to compete with those observatories. It almost looks like the AAVSO approach is a shotgun approach. Each one of those systems, save the Star Analyser, is significant. Without a team or project for each one, I wonder how anything will get done. Also glaringly absent from the equipment list are the LISA and Lhires III spectrographs.

As I recall large institutions assign graduate students to such projects and their advisors would be the leaders. Anyone who has done graduate work well knows they usually end up nearly selling their souls for the project. They usually get paid little if anything for near slave labor. Where is similiar help to come from for the AAVSO projects? I do not think this is the same as "if you build it they will come." For me there is no financial reward or even promise of an advanced degree. I love physics and astronomy. I can go out in my backyard and take specra of stars and see the soul of the stars. I find that most exciting. Being part of a project and pubishing data is a great ego trip, but not required for me.

This also leaves many of the AAVSO members, who would like to get involved, a bit out in the cold. What can they do? Spectroscopy tends to be a personal learning experience.

As Dr. John Martin has pointed out spectroscopy produces very differnt data than photometry and must be handled differently. As I look at the proposed equipment my thoughts are there will need to be dedicated teams with project leaders associated with each system to define projects, collect data and provide an analysis. I do not think there are suffiently qualified and interested people within the AAVSO to handle all that equiment or even a small part of it. From my experience each project MUST have a leader who is knowledgable and inspired. Without that, the equipment and/or data will gather dust.

So to me it looks like there are three topics here:
1. AAVSO spectroscopy equipment, how will it be used?

2. Getting members interested and up to speed on spectroscopy along with helping them with their personal equipment and software.

3. Archiving of spectrometry data.

What next?

Jeff

AAVSO spectroscopy
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HQA
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Joined: 2010-05-10

Ken mentioned the many spectrographs that the AAVSO already has, and raises the question of how we intend to support them.  I have been on travel for the past month, and so have not been able to respond to the many interesting posts that have been made on this thread.

My preference is always to use existing standards and technology whenever possible.  BeSS and others have made a great start towards defining the necessary keywords and file types, and frankly, storing spectra is not much different than storing images - more complex than individual photometric measures, but not that hard.  To me, the real issue is planning; developing an approach that works for the targets of interest to the AAVSO and providing scientific quality results that are accessible by the community.  I expect to be involving key players in both the amateur and professional communities in the near future to  come up with a good solution.  In the meantime, I'll see if we can't get our store/retrieve option updated and released, so at least you have a home for your spectra.

Arne

AAVSO Spectra database
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TCB168
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Joined: 2010-07-26

I agree with what has been stated above.

There are currently quite a few programs requesting spectra. These include the T Tauri stars, HD5980, and V4018 Sgr.

The other role is confirmatory spectra of novas, supernovas etc.

I assume that the investigators that request this could state what processing and resolution that they want. The data could easily be in the format that BESS uses as realistically the only people that have the equipment and expertese to submit data will be aware of the BESS format and probably already submitting to that database.

As stated before, the AAVSO has a robust net presence that hopefully will be around for many years. This makes it ideal to host the spectra obtained for the suggested programs plus nova and supernovas as needed. Even at that level the support of the AAVSO would be very useful.

Cheers

Terry

What can we do to maintain
Ken4optics's picture
Ken4optics
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Joined: 2012-04-02

What can we do to maintain the momentum?

Do we need to better explain to the AAVSO general membership the benefits of spectral observations?

What about some review of the recent amateur data being collected on SuperNova?

AAVSO 49 Bay State Rd. Cambridge, MA 02138 aavso@aavso.org 617-354-0484