spectro Histoire de la spectreheliographie amateur

gabal · 15 novembre 2009

Fredrick N. Veio a entrepris d'écrire un livre sur la spectroscopie amateur. Ici vous trouverez un chapitre sur la shg avec quelques références bien connues ici.

(Tiré se la liste Spectro-L)

"From: fveio@hotmail.com

To: fveio@hotmail.com

Subject: History of Doppler Shift and Zeeman Effect by Amateurs

Date: Fri, 13 Nov 2009 16:50:30 -0800

History of Doppler Shift and Zeeman Effect Observed by Solar Amateurs

Fredrick N. Veio, November 2009

Astronomy has been my hobby for the past 63 years, having various kinds of experience with optics and sky events, am now 79 years old. My interest in the spectrohelioscope (SHS) began in 1962, looking for something different in amateur solar astronomy. Built a compact SHS in 1964, portable, simple construction, low cost, $300, published in Sky and Telescope, January of 1969. Also Journal of the B.A.A. volume 85, page 242, 1975. Wrote a lot of letters to interested amateurs of the world in the following years. Some new designs were sent to me, and they were included in a booklet on the SHS, first published privately about 1972, selling for two dollars.

The following statements are presented to the solar amateurs in order that they become aware that they can do wonderful H alpha observing with a SHS. Do not need big solar instruments in most instances. A few skilled amateurs in the world are leading the way for you. Since 2000 I have been pushing information through the Internet. Amateurs themselves have developed new compact designs. I can not do it all myself. I do not have the money, the energy, the time and am also getting old. Go to their web sites for details of construction, also spectroheliograms with fine solar disk detail. Do a google search, type in their names, also solar atlases, solar spectroscopy, other things.

The spectroheliograph was invented by Dr. G. E. Hale and Dr. Henri Deslandres about 1892. Both worked independently, the former from the USA and the latter from France. The visual SHS was invented by Hale in 1924. The French magazine l'Astronomie a few years ago had three excellent articles on the history of the development of the spectroheliograph with French references going back to around 1880, written by Dr. A. Dollfus, famous French astronomer. Go to Philippe Rousselle, http://www.astrosurf.com/spectrohelio.'>http://www.astrosurf.com/spectrohelio.

The Hale SHS design of 1924 has a two mirror coelostat, 18 feet f.l. (5.4 meters) telescope lens, 13 feet f.l. (3.8 meters) spectroscope with two concave mirrors, a 600 gr/mm grating of 50x50mm area, linear dispersion 4A/mm in the first order. Anderson prisms and Hale oscillating slits used for the solar image synthesizer. Hale published four articles on the SHS, the first one in the Astrophysical Journal, vol. 70, page 265, 1929. He also used the painted rotating glass disk synthesizer, eight inches (200mm) in diameter with 150 slits for three passbands, a shutter with 50 slots selects one of the three passbands.

The compact SHS by Veio, 1964, is a heliostat mirror, 9 feet f.l. (2.7 meters) telescope lens, 75 inch f.l. (1.9 meters) spectroscope Littrow lens, 1200 gr/mm grating of 32x30mm area, dispersion 4A/mm first order. Veio invented the 4 inch (100mm) rotating painted glass disk with 24 slits of 0.5A H alpha passband for the synthesizer. Years later some amateurs had a more compact SHS with a 50 inch f.l. (1.2 meters) telescope lens and a 40 inch f.l. (one meter) spectroscope lens, various gratings (600 gr/mm, 1200 gr/mm, 1800 gr/mm, 2400 gr/mm) of choice for different purposes. Each has certain advantages.

Mt. Wilson Observatory, California, 60-foot Tower installed in 1906, with 30 foot f.l. spectroscope and 60 feet f.l. telescope of 12 inch diameter (300mm)), 300 gr/mm grating, dispersion about one A/mm in the third order; 150-foot Tower made ready in 1912, with 75 foot f.l. spectroscope and 150 foot f.l. telescope of 12 inch diameter (300mm), 600 gr/mm grating, dispersion varies from one A/mm in the first order to 0.1A/mm in the 10th order. They are very powerful solar spectroscopes, not SHSs. They can be used in the spectroheliograph mode too.

M. A. Ellison and F. J. Sellers both of England made a professional SHS, about 1940, 18 feet f.l. (5.4 meters) telescope achromat, 16 feet f.l. spectroscope achromat, 600 gr/mm grating. After WW II an engineer in Tasmania made a similar instrument. Original gratings finally were copied using a resin replication technique in 1957 by Bausch and Lomb, Inc, reducing the cost by 90%.

In 1964 an original B and L grating of 1200 gr/mm and 32x30mm (1.2x1.2 inches) area would sell for $1000; could be sold as a replica for $96. The same 32x30mm grating now would be about $400 due to inflation. Edmund Scientific about 2000 came out with good replica gratings at a lower cost, about half. Classical and holographic gratings are similar in performance; the replication technique is the same.

B. C. Parmenter and W. A. Semerau of the U.S.A. each made a professional SHS about 1959, telescope 18 ft f.l.(5.4 meters) and spectroscope 13 feet f.l.(3.8 meters), 600gr/mm grating, 50x50mm (2x2 inches) area. Veio made a compact SHS a few years later, telescope 9 ft f.l. (2.7 meters) and spectroscope 6 feet f.l., 1200 gr/mm grating, 32x30mm area. Veio published his design in Sky and Telescope, January of 1969. Others amateurs followed with compact designs in later years.

Veio had a Zeeman article published in ORION, Swiss Astronomical Society magazine, 1975. My thanks to Dr. Harold Leinbach of NOAA. He wrote for a copy of Veio's small 60 page booklet on the SHS in 1975, and he mentioned that his professional SHS would show the Zeeman effect visually, 8 inch (200mm) concave telescope mirror 18 ft f.l.(5.4 meters), 8 inch (200mm) concave spectroscope mirror, 5 feet f.l.(1.6 meters), 1800 gr/mm grating, 50x50mm area. Veio did not at all believe it was possible until Leinbach told him so. He thought a monster solar scope was needed. Not so. Read on.

Veio visited Mt. Wilson about 1982. He was given a tour, saw the 60 inch reflector, also the 100 inch reflector, and the 60-foot and 150-foot Solar Towers. In the latter tower, Veio was given a demonstration of seeing the Zeeman effect (magnetic field splits the spectral line into two lines) with the entrance slit on a sun spot on the solar disk. The Zeeman effect was easily seen.

With the Polaroid before the eye and in the hand and looking through the long focal length eyepiece (about three inches), the left side of the split Zeeman line was not seen but the right side of the line was visible. Change the Polaroid 90 degrees, and the left side of the line was seen but not the right side. Remove the Polaroid from the eye and the spectral line with the left and the right sides both seen with a space in between. Near the entrance slit a 1/4 wave retardation plate changes the circular polarized light into linear polarized light. The Polaroid blocks out one side of the line and passes the other side.

Veio registered on the Internet with Yahoo in 1999, forming the first SHS web site for amateurs; then a year later registered an email account with Hotmail. My thanks to Paul Spillane for showing me how to do it. We met at a chit chat group at noon at Taco Bell in 1999. The number of SHS members at first was about 20. A year later, still about 20. Two years later about 50. Then the following year a surge of members up to about 125. Now it is about 250 members. Not a lot but there was almost no SHS and no web sites before 1999.

Leonard Higgins built a SHS in 1998. He lives in the city of Napa, north of San Francisco. Anyway, his telescope is a 5 inch (125mm) concave mirror of 9 ft f.l. (2.7 meters) with a 2X Barlow to give 20 feet (6 meters) equivalent f.l. Spectroscope is one 8 inch (200mm) concave mirror and 8 feet f.l. (2.4 meters). Grating is 1200 gr/mm, 50x50mm area, dispersion 3.2A/mm in the first order.

In the summer of 1999 in the second order, we observed our first Zeeman line in the green of the solar spectrum. It was just a widening of a line in the umbra, sort of boring to look at. We did not identify the wavelength of the line. In 2000 we again found a Zeeman line, not identify the line. We had looked for other Zeeman lines but there just are not too many to observe with a limited SHS. In 2002 we decided to identify the Zeeman lines and found some in September and in October. More lines were seen in March of 2003, also in following months and in 2004. First Zeeman article by amateurs, Fredrick Veio and Leonard Higgins, was published in the Journal of the B. A. A., February of 2006.

About 1999 Veio had read an article in an Astrophysics Journal, about 1906, that Dr. Pierce used a 23 inch refractor at Harvard University. He listed about 600 Zeeman spectrally, visually sensitive lines. He had a 36 inch f.l. (900mm) spectroscope and an 800 gr/mm grating, 60x100mm, attached to the 23 inch refractor. Dispersion 5A/mm in the third order. His article was helpful to locate some Zeeman lines. In a physics laboratory on the earth there is no pressure or temperature effects on the gases, so in a strong magnetic the spectral lines appear sharply in emission, that is, the Zeeman effect. On the sun there are pressure and temperature conditions that widen the dark absorption Zeeman lines, the inverse Zeeman effect, making a different appearance.

About 2000 Toshio Ohnishi of Japan was kind to put all the 119 pages of Veio's SHS book on his web site. Dr. J. Christopher Westland of Hong Kong soon followed to put the book on his web site. Ohnishi web site is http://www.2s.biglobe.ne.jp/~t-oni/shs.

For more details of SHS discussions by Veio and H alpha spectroheliograms by other amateurs, go to http://www.eyes-on-the-skies.org/shs. Web site of Mike Rushford, California.

In the winter of 2002, Veio sent a short list of Zeeman lines to Philippe Rousselle of France. In the spring of 2003 Phil Rousselle confirmed the Zeeman effect with his compact shgraph, http://www.astrosurf.com/spectrohelio. Also detected the Doppler shift. Later months of 2003 Christian Buil did Zeeman effect and Doppler shift, http://www.astrosurf.com/buil. Tanaka Kazuyuki of Japan, August 2003, Zeeman effect and Doppler shift, http://www.5f.biglobe.ne.jp/~kztanaka/littrowsp

. Dieter Goretzki of Germany, March 2004, Zeeman effect and Doppler shift, http://www.astrospectroscopy.de/goretzki. Roger Marcon of Brazil in 2003, saw the Doppler shift. Toshio Ohnishi of Japan translated Veio's Zeeman article into Japanese in 2007, and it is on his web site, listed in above paragraph.

About 1998 Veio received from Brian G. W. Manning, England, an excellent spectrograph, dated about 1975, of the Doppler shift of the sodium lines as viewed with the slit on the east and the west edge of the solar limb. He is the first amateur to do it. He has a compact SHS. Veio told other amateurs of this possibility, and the Doppler shift was confirmed in 2003 by Phil Rousselle and C. Buill both of France, also Rogerio Marcon of Brazil.

Our deepest thanks to Brian Manning to pioneer this solar event and to share this information. He has a 600 gr/mm grating used in the fifth order and Kodak 2415 film, very fine grain which is needed. Telescope about 50 inch f.l., spectroscope 40 inches f.l.(one meter), 600 gr/mm, slit about 25 microns. By the way, Brian is the first amateur to make an original grating of good quality, 50x60mm area, 600 gr/mm.

Some physics professors with students at a few colleges in the world observed the Zeeman effect and the Doppler shift. Cornell University of England in August 2003, http://www.astro.cornell.edu. Also Middlebury College, Vermont, USA, about 1992, http://www.cat.middlebury.edu/~PHManual.

As best as I can remember, about 1970 an aerospace company in the Los Angeles area of California built a folded up spectroheliograph, vacuum optical folded up design, very compact. With TV camera and magnetic hard drive they took solar magnetograms of sun spot regions and projected them in real time, not the slow photographic way as on Mt.Wilson. They donated the instrument to San Fernando College, now S. F. State College. Oxford University of England made a compact spectroheliograph, using a 12 inch Cassegrain reflector of quartz primary and quartz secondary, with spectroscope, observed the Zeeman effect too, published in the Journal of the B. A. A. about 1960.

Of special note is Andre Rondi and son Sylvain Rondi of France, http://www.astrosurf.com/rondi.'>http://www.astrosurf.com/rondi. They built a compact shgraph using a web cam in 2004. Took excellent H alpha spectroheliograms in 2005. Then they successfully made the first amateur solar magnetogram in 2006.

They used a small area of the sun with a sun spot group. Selected professional wavelengths. Took several linear polarized spectrograms in left and in right light, then separately stacked the left and the right images, then combined together for a magnetogram. Excellent, about 6 sec/arc detail. http://www.astrosurf.com/rondi. Available in French and in English. Andre has a math degree and Sylvain has a astronomy degree, such education being needed in order to know what to do as described in the journals.

In spring of 2002 another Frenchman, Daniel Defourneau, now retired, financial computer specialist, created a software, called the 2 D (two dimensions), in order to acquire an H alpha spectroheliogram. His very compact shgraph is easy to copy, low cost. Telescope 800mm f.l., spectroscope 400mm f.l., 2400 gr/mm grating, 30x30mm area. He has a fixed shgraph on a rigid tripod and pointed at the sun, which drifts across the front of the telescope. RA drive not used. With web cam and computer, he takes a series of H alpha spectrograms. His computer selects just the H alpha line, combines them line by line together into a spectroheliogram. He gets about 7 sec/arc detail. But he gets an instant shgram, that is, in real time in ten minutes of processing time.

Christian Buil tried the technique in the autumn of 2002, made some technical improvements, called it the IRIS software, which works also excellent. All email messages are on a French web site for reference. Defourneau, Buil and Alex Canicio deserve much credit for introducing a new method for amateurs for recording solar events in real time. Canicio also of France prepared a faster computer software in order to shorten the shgram processing time from about ten minutes to about two minutes.

Defourneau recently, October of 2009, with his shgram observed a flare with Moreton waves (magnetic transverse waves, originate in the lower corona) on the solar disk in H alpha light. He is the first amateur to do it. He also with his compact shgraph took the solar disk showing the solar limb Doppler shift in color, in red and in violet light for the receeding and approaching solar limbs respectively. He is first to do the latter with modest equipment. Other amateurs demonstrated the Doppler shift just in the spectroscope mode, not yet the solar disk mode, that is, the spectroheliograph mode.

So in the past few years a group of French solar amateurs showed many solar events with a compact SHS, or a shgraph. Hats off to Philippe Rousselle, Andre and Sylvain Rondi, Christian Buil, Daniel Defourneau and Alex Canicio. And to others as listed above.

About 50 years ago when I was a student, I visited the University of California astronomy library often. I saw a small Astronomy magazine published by a group in England. On the title page was a few H alpha grams by B. A. Manning, taken with his compact SHS (50 inch f.l. telescope lens, 40 inch f. l. spectroscope lens). I wrote to the editor, and he gave me Manning's address. Writing to him was a reward with an article describing his design in Journal of the B. A. A., volume 92, 1982. He invented the Manning solar synthesizer.

It is important to realize how wide is the dark core of certain wavelengths. The H alpha line is 0.6A wide, the H beta 0.4A wide, Na lines 0.1A wide, the Mg lines 0.05A wide, easy Zeeman lines 0.03A wide. With a 75 inch f.l. (1.9 meter) spectroscope lens and a 2400 gr/mm grating, the linear dispersion is 1.5A/mm, first order. The Zeeman line is easy to resolve in the visual mode of the human eye.

Cheers, Fredrick N. Veio "

gabal · 8 décembre 2009

Histoire :

History of Spectrohelioscopes by Amateurs

Fredrick N. Veio, May 2009

The spectroheliograph was invented by Dr. Henry Deslandres (1884) of France and Dr. G. E. Hale (1883) of America. Professional observatories made excellent spectroheliographs, having long focal length optics and big gratings. The visual counterpart was invented by Dr. Hale about 1924. He wrote four articles in the Astrophysical Journal in the following years.

Hale, G. E., Astrophy. J. vol. 70:265 (1929). Basics about SHS.

Hale, G. E., Astrophy. J. vol. 71:73 (1930). Observations with a SHS.

Hale, G. E., Astrophy. J. vol. 73:379 (1931). More observations.

Hale, G. E., Astrophy. J. vol. 74:214 (1931). Important technique to photograph the sun in H alpha light, using a prism and lever system with camera for excellent spectroheliograms.

The Hale spectrohelioscope had a two flat mirror coelostat, a telescope lens of five inch diameter (125mm) and 18 feet focal length (5.4 meters), also a spectroscope of of two concave spherical mirrors of three inch diameter (76mm) and 13 feet f.l. (3.8 meters). Grating was an original of 2x3 inch (50x76mm) area, 600 gr/mm at 5000A blazed wavelength. The linear dispersion was 4.0A/mm in the first order. Straight line optical arrangement. Solar disk detail in H alpha light was about 2 arc/sec, having a two inch (50mm) sun image on the entrance slit.

In the past, the limiting factor for amateurs was the gratings were originals and very expensive. A few amateurs were lucky to have an original grating loaned to them.

In the list below the mention of medium focal length optics is the telescope is about 2.5 inch diameter (60mm) with nine feet f.l. (2.7 meters), and the spectroscope lens is about two inches (50mm) with about 75 inch f.l. (1.9 meter). Some amateurs made a more compact design with the telescope about four feet f.l. (1200mm) and the spectroscope about 40 inches f.l. (one meter). Gratings from Edmund Scientific were 1200gr/mm, 1800gr/mm and 2400 gr/mm, visual blazed. The focal lengths can be plus or minus a bit, not at all critical.

When I was a young man, the moon was observed with ten inch (250mm) Newtonian and six inch (150mm) Newtonian telescopes. The six inch gave good views of the moon. It seemed to me that if a medium SHS was about half the dimensions of a Hale SHS, the compact design should show reasonably good image detail on the solar disk. So I decided to make a compact SHS in 1962, reading what little was available. The Bausch and Lomb replica reflection grating of 1200 gr/mm, 30x32mm area, 5000A blazed, was bought in 1964, 96 dollars, and the two lenses I made in the same year. Simple eyepieces were used, 2.5 inch (60mm) f.l. achromat for the spectroscope mode and 4.5 inch (110mm) f.l. for the spectrohelioscope mode, almost the same as used by the Hale SHS. Does not have to be exactly the same, just close. Divided telescope nine feet f.l. by eyepiece 4.5 inch f.l., you get the working power of 24 X for the solar disk with the Veio SHS.

The half design was a complete success for the sun in H alpha light. The solar disk visually showed about 5 arc/sec detail, solar image diameter was 25mm, and the solar spectrum in brilliant detail, linear dispersion 4.0A/mm, first order, same dispersion as Hale SHS. Tilt the grating to higher orders gave much finer detail in the solar spectrum. Flares, filaments, surges, prominences were all easily seen. The reason the compact Veio design worked good was because all the main solar disk features are about 5 arc/sec or larger. A single mirror was used for the heliostat.

There were very few SHSs in the world, so very few amateurs ever had the chance to just see the solar spectrum in fine detail, let alone the solar disk in H alpha light. I decided to change that limited situation. From 1964 on I made contact with amateurs through clubs mentioned in Sky and Telescope, also amateurs in the world who sent in reports to the magazine. My design was published in Sky and Telescope, January issue of 1969. About 1972 I wrote a small 56 page book and advertised it in Sky and Telescope, and many amateurs wrote to me, selling it for about two dollars.

The following list of SHSs may not be be complete. If there are omissions or errors, let me know. Between 1967 and about 1998, I wrote about nine thousand letters to amateurs, trying to encourage some to make a spectrohelioscope. About one new SHS constructed every two years. From 1999 via the Internet to the present with a hotmail.com web site, I had emailed about ten thousand emails to amateurs, more quickly stimulating amateurs, and more started fabrication of same. Paul Spillane, a friend, informed me how to sign up and to use the Internet in 1999. I also have a groups.yahoo.com/spectrohelioscope for amateurs to exchange ideas.

Try a google search, type in the name of an amateur, get his web site and other things. Type in Zeeman effect, Fredrick Veio, other names, get a quick useful list of information of amateurs of the world.

And here is the list of amateur SHSs as best as possible.

1924, Dr. George E. Hale, first full sized SHS in the world, standard fixed layout, USA. In the following years he had about 30 such instruments set up in various parts of the world.

1938, F. J. Sellers, England, long f.l. optics, fixed installation. Used Sellers synthesizer.

1940, Rev. M. A. Ellison, England, long f.l. optics, fixed.

Bausch nd Lomb Co., high quality replica gratings commercially available, 90% theoretical resolution or better, made at Richardson Grating Laboratory, USA. An original grating of 30x32mm area on a 50mm round blank, 1200 gr/mm, would be about 1000 dollars, but a replica of same would be about 100 dollars.

1963, high quality holographic replica gratings available.

1958, B. C. Parmenter, Spokane, Washington, USA, standard Hale SHS design with long f.l. optics., fixed location. About 24 years later he moved to Arizona and constructed a new design, the largest in the world by an amateur at that time. The heliostat was large. The telescope BK 7 lens was ten inch diameter (250mm) and 26 feet f.l., with a Barlow that produced 36 feet equivalent f.l. (10.8 meters) for a four inch diameter (100mm) sun image. The spectroscope BK lens was about four inches (100mm) and ten feet f.l. (3.3 meters). Grating, 76x76mm. An investment of building, fine machine shop parts, excellent optics, roughly $30,000 or more. Most of the work done by Parmenter.

A brief note about a sun image. Nine feet f.l. optic (2.7 meters) gives one inch image (25mm). An 18 feet f.l. (5.4 meters) produces two inch image (50mm). And so on.

1959, Walter J. Semerau, New York, medium long f.l. optics for first design on heavy equatorial mount. Then later long f. l. optics, sophisticated design with fixed installation on the side of his home and into the basement. Sky and Telescope, issues about 1959 to 1962.

1962, Malcom M. Maner, Florida, long f.l. optics in a straight line, fancy fixed layout.

1962, Fredrick N. Veio, California, medium f.l. optics in a straight line, very portable, wood parts, very simple and low cost construction, expences about $300, made his two lenses. Sky and Telescope, January of 1969. Highly simplified rotating glass disk, painted black, 24 slits of 125 microns for 0.5A passband in H alpha light.

1966, Harold Hill, England, long f.l. optics, standard Hale design, fixed in his home.

1970, Jean Nicolini, Brazil, long f.l. optics, fixed. He worked in a commercial bank. Spoke Portugeuse, Spanish, French, Italian. His English was average. I had some experience with Spanish, German and French. It was easier for him to write to me in French and me to him in English.He was educated in France. His father was Portugeuse, his mother was Italian, and so it goes.

About 1980 I had a letter from an amateur in Poland. He also understood German but only a little English. I did not know Polish. I told him I knew German and French. He told me never to use German. So I wrote to him in English, and he wrote to me in German. I had a famous amateur in Chechoslovakia, knew German. I did not know Chech. So I wrote to him in German, and he wrote to me the same language. Again so it goes. Janos Klepesta.

Cesare Greco, Genoa, Italy, an Italian group started with long f.l. optics, fixed.

1972, Fred Veio wrote a small 56 page book on the SHS, about two dollars, later years expanded to 60 pages, then 84 pages, finally 120 pages about 2000. Has complete plans, all new synthesizers, and so on. I sold it at cost. Over 2000 copies are scattered in the world. Book is free on the Internet,

http://www.astrosurf.com/spectrohelio'>http://www.astrosurf.com/spectrohelio Philippe Rousselle web site, Metz, France.

http://www.eyes-on-the-skies.org/shs'>http://www.eyes-on-the-skies.org/shs Mike Rushford, Calif., USA.

The book was originally put on the web site of Toshio Ohnishi of Japan, year 2000. I sent him all the xerox pages of my manuscript. Then Mike Rushford down loaded it on his web site. Next Dr. J. Christopher Westerland of Hong Kong put it there too from about 2000 to 2007, and on SONNE magazine in Germany. To the doctor I sent all kinds of excellent, original photos of the sun sent to me and taken by amateurs, other stuff too. So you can see first hand what amateurs with a SHS can do.

1971, Brother Theodore van Poecke, Huybergen, Netherlands, medium f.l. optics, portable. He has my original SHS optics. Gave to him for free. He was a Catholic teacher. Had good English. He was first in Europe for a compact, portable, low cost design.

1971, Dr. Donald Mruk, Mass., medium f.l. optics, portable, built it in high school at 17 years.

1972, Randy Shivak, Ohio, medium f.l. optics at first, then later long f.l. opitcs, set up on the side of his home, real neat, fixed.

1975 Achim Gruenberg, near Dresden, Germany, long f.l. optics, fixed.

1975, Ulrich Fritz, Schwaikheim, near Stuttgart, Germany. Veio's 60 pages translated into German.

1975, Fred Veio decided to make a more compact SHS, telescope 50 inch f.l. (1250mm) and spectroscope 40 inch f.l. (one meter), grating 1200 gr/mm. The synthesizer was the 4 inch diameter (100mm) rotating glass disk, painted black, 24 slits cut in the paint, same disk as the SHS of 1964. I made my own painted glass disk with a simplified cutting technique. The SHS design with a 75 inch f.l. spectroscope lens works very good with the 4 inch rotating disk synthesizer.

But the more compact SHS design with 40 inch f.l. spectroscope, the 4 inch synthesizer does not function so well. The center to center distance of the slits was too wide, namely 3 inches (76mm). So I made a spectrograph, got exposure data of the spectrum and for a future spectroheliograph. A few years later I learned that the Brian Manning synthesizer would be the correct synthesizer because the entrance and the exit slits are closer together optically, 1.5 inches (37mm). And about 1990 Toshio Ohnishi of Japan had a new end-folded oscillating slits that would be good too with a 40 inch f.l. lens.

1975, Brian G. W. Manning, Worcestershire, England, medium f.l. optics, portable. He invented the Manning solar image synthesizer, no vibrations, easy to build, excellent. With Kodak 2415 H alpha film, high resolution and high contrast (about 450 lines/mm), he got spectroheliograms of 3 arc/sec detail. Passband 0.6A. Most excellent for a compact instrument. He put his film SLR camera next to the eyepiece, focused at infinity, lens wide open, then the slits moved sideways across the solar disk, about three to six seconds exposure.

1975, Toshio Ohnishi, Kawanishi, Japan, medium f.l. optics, portable. About 1990 he invented the Ohnishi synthesizer, having folded ends with oscillating slits, similar to but not the same as the Hale oscillating slits. Met him in San Francisco about 1995, took him to Lick Observatory, saw the 36 inch refractor (0.9 meter). He was in awe, me too.

1975, Prof. Wolfgang Woess, Linz, Austria, medium f.l. optics, portable.

1976, Janos Papp, Budapest, Hungary, medium f.l. optics, portable.

1975, Dr. Harold Leinbach, NOAA, with his full scale SHS, he observed the Zeeman effect. He wrote for a copy of my book. He related some of the details to me with his SHS. Thereafter I would try to inform other amateurs to do the same. I first saw the Zeeman effect at Mt. Wilson about 1982, using the 150-foot Solar Tower. I first viewed the Zeeman effect with a SHS in 1999. Leonard Higgins and I did it with his new SHS. In 2003 with my new very large solar spectroscope, I saw the Zeeman effect too. Telescope is 6 inch (150mm) concave mirror of 16 feet f.l. (8 meters) with 2X Barlow to give 16 meter equivalent f.l. Spectroscope is two concave mirrors of 8 meters f.l. Grating 100x100mm.

1977, Jeff Simsovic, NM, long f.l. optics, fixed.

1979, Klass Honders, Netherlands, medium f.l. optics, portable.

1980, Heinrich W. Beeker, near Mainz, Germany, medium f.l. optics, fixed and set up in the attic of his home. He completed his instrument about 1995. He invented the Beeker coelostat design, two mirrors, more compact than other coelostats. Similar to Zeiss coelostat but mechanically different design, very clever.

Mike Rushford, Calif., long f.l. optics, fixed. http://www.eyes-on-the-skies.org/shs

Now the Veio web site for SHS by amateurs of the world. Server site Ron Wickersham, California.

1980, Walter Piorkowski, Illinois, medium f.l. optics, portable.

1980, Maurice Gavin, Surrey, England, medium f.l. optics, portable.

1981, Dr. H. R. Soper, Isle of Man, England, standard Hale SHS design.

1982, Jeffrey Young, Calif., medium f.l. optics, portable. Invented the Young knodding mirror synthesizer, which is equal to Anderson prisms synthesizer. His design is easier and cheaper to make, less skill to set up. A breakthrough for solar amateurs. He visited me about 1990. I live north of San Francisco about 125 miles.

1985, Cmdr. Henry R. Hatfield, Kent, England, long f.l. optics, fixed set up. About ten years later he rebuilt the whole design, using the Arcetri side slit moving synthesizer. Articles in Journal of the British Association.

1990, Dr. Otto J. Lieder, Lahrs, Germany, medium f.l. optics. Due to health, not finish it.

1992, Michael Hill, Mass., medium f.l. optics, portable.

1992, Vittorio Lovato, Voghera, Italy, medium f.l. optics, portable. I met him in San Francisco about 1998, took him up to Lick Observatory, saw the 36 inch refractor, he was amazed.

1992, Rogerio Marcon, Campinas, Brazil, long f.l. optics, fixed set up. Used Manning synthesizer to excellent effect.

1994, Gote Flodqvist, Farsa, Sweden, medium f.l. optics, portable. Invented the Flodqvist synthesizer.

1998, Philippe Rousselle, Metz, France, medium f.l. optics, portable, 2 arc/sec detail on the solar disk. He used a linear array of 14 micron pixels, sun drifted across the entrance slit in RA. Telescope fixed towards the sun, computer captured all the linear array sections of the sun, built up a full image on the monitor, excellent. He is the first amateur to use a linear array. In 2001 he rebuilt his SHS. http://www.astrosurf.com/spectrohelio He has a mirror system in front of the entrance slit in order to reflect away extra solar heat from the sun image.

1995, Pierre Barthelemy, le Pin, France, medium f.l. optics, portable.

1996, Ken Florentino, Colorado, medium f.l. optics, portable.

1997, Kurt Tiede, Ludwigsau, Germany, medium f.l. optics, portable.

1998, Leonard Higgins, Napa, Calif., medium f.l. optics. Used the Young synthesizer. Went to Riverside Telescope Makers Conference, first place for his SHS. http://www.spectrohelioscope.org

Veio and Higgins easily observed the Zeeman effect in 1999, first amateurs in the world.

2002, Jonathan Slaton, USA, long f.l. optics, fixed.

2002, David Groski, Delaware, medium f.l. optics, portable.

2002, Fredrick Veio made a very large solar spectroscope, heliostat 8 inch (200mm) 1/6 wave, telescope 6 inch (150mm) concave mirror of 16 feet, with -20 inch Barlow to give equivalent 36 feet f.l. (about ten meters), 4 inch (100mm) sun image at entrance slit. Spectroscope section 16 feet f.l., 4x4 inch (100x100mm) grating, about $900, 600 gr/mm, blazed 1.6 micron, linear dispersion 0.6A/mm 4th order. All semi-portable, all simple wood construction, about $3000 total. Half paid by a friend Norman Kay of Los Angeles, other half by Veio. If I do it over, could build for about $2,000. Zeeman effect seen easily. The design was partially rebuilt in 2004. Folded up U-shape design.

2002, spring time, Daniel Defourneau, near Paris, France, software engineer with excellent expertise. He used special techniques for infrared vacuum research, applied a modified software to taking H alpha spectrograms of the sun. He had medium f.l. optics. He used a web cam to take a series of spectrograms, let the sun drift across the field of view of the fixed telescope and spectroscope, had about 1500 spectrograms. His computer selected the H alpha line in all the spectrograms, line by line bulit up a spectroheliogram in H alpha. He published his 2D software on a French web site. A breakthrough for amateurs. http://www.astrosurf.com/cieldelabrie/sphelio

2002 several months later, Christian Buil read Daniel's method and tried it with success. Buil made some minor changes and published his version as the IRIS method. Buil helped to popularized the technique. To process one H alpha image takes about ten minutes. About 2004 Jose Ribeiro simplified the software so that the time required to process one image took about two minutes. http://www.astrosurf.com/joseribeiro/Eespectroheliografia

I try to garner different kinds of technical articles and pass them on to amateurs. Examples follow.

2002, Veio read an article in Solar Physics, professional magazine, about 1980. With Kodak film they take a He I spectroheliogram in the line of yellow helium, than another one angstrom off of the line, subtract one photo from the other and yields the helium plage easily in absorption. Not need a flare, just use the plage. Veio told Rousselle to try the same with his instrument, and he was successful. Christian Buil tried it in 2003, and he was successful too.

Summer of 1999, Veio and Higgins with the latter's SHS observed the Zeeman effect in a sun spot. Summer 2000, again saw the Zeeman effect. September of 2002, they decided to identify the spectral wavelength with the first lines near the H alpha line. March of 2003 more lines were viewed. Veio sent the wavelengths to Phil Rousselle in winter of 2002, and he confirmed them with his spectrograph/spectroheliograph in summer of 2003. http://www.astrosuf.com/spectrohelio Veio sent an article to the Journal of the British Astronomical Association, February of 2006, first Zeeman effect article by amateurs.

About 1998, Brian Manning sent me a 1975 spectrogram of the Doppler shift of the sodium lines with the entrance slit on the east and the west limbs of the sun. Grating was 600 gr/mm and used in the fifth order. He got excellent results. In 2002 I informed Rousselle to try the same, and he achieved success. In 2003 Buil and Rogerio Marcon of Brazil tried and had success too. Thanks to Manning to share with us all, for I can not do it all myself.

2005, Andre and Sylvain Rondi, father and son, used medium f.l. optics, portable. They got excellent H alpha spectroheliograms. In summer of 2006, they performed the first amateur solar magnetogram. Used a small area aroud a sun spot, about 3 min/arc by 3 min/arc area, which is sufficient. They used a web cam, taking several photos in right polarized light, then several photos in left polarized light, then stacked the right images, staked the left images, combined the right with the left to produce a magetogaqm. They used different wavelengths just as the professionals do. All detail on their web site, http://www.astrosurf.com/rondi Excellent.

Many new solar image synthesizers are now available. Each synthesizer can be used only with certain spectroscope designs. So design your SHS carefully. Edmund Scientific gratings are less expensive than by some companies, saving monies. My book is free with needed informations. Read it carefully.

I used the rotating glass disk synthesizer in 1964, 4 inch diameter (100mm) and painted black, 3mm thick glass. It had 24 slits of 125 microns for 0.5A passband. Mount the 4 inch disk on a flange, and mount the 4 inch disk with flange on the axle of a Bodine motor of one revolution per second. The glass disk worked excellent, but it is delicate to make. I suggest about a 3 mm thick metal aluminum disk, slits cut with a cutting saw about 0.008 inch (200 microns) thick. The cutting saw can be honed down to 0.006 (150 microns). I never published the cutting technique. The original glass disk was 8 inches (200mm) diameter, about 150 slits, used by Hale. I highly simplified the design to 24 slits so it is much easier to make.

In the past several years, many professional solar observatories posted their various atlases of the profile of the solar spectrum, also different atlases of all the wavelengths. All on the Internet for free. Rousselle has the solar wavelength book by Dr. C. E. Moore on his web site. A few years later Quester Corporation also the same wavelength on their web site.

This presentation is no by means final, but it gives an idea of what has happened in the past 40 years or so. I am so happy, being almost 79 years, getting slower and slower. Younger person are entering into this solar work.

Cheers, Fredrick Nall Veio (Nall is my mother's maiden name)

One more detail. Camiel Sverijns of the Netherlands made a compact SHS. Beautiful.

Home.hetnet.nl/~c.severijns/Astronomy. It is expensive. You do not have to do it his way. And Alex Canicio made a fast software for processing H alpha images, faster than Buil method. Alex lives in the south of France. http://www.astrosnap.com He understands good English. acanicio@astrosnap.

Slight revisions, December 2009.

gabal · 8 décembre 2009