AAVSO: Solar Bulletin June, 2001

Solar Bulletin
THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS - SOLAR DIVISION
Carl E. Feehrer, Editor 9 Gleason Rd. Bedford, MA 01730	Email: cfeehrer@hotmail.com ISSN 0271-8480

Volume 57 Number 6	June 2001

Table I. Mean Sunspot Numbers for June
[boldface = maximum, minimum]

Table II. June Observers

Day	N	Raw	s.d.	K-corrected	s.d.	s.e.
1	33	82	5.4	66	4.0	0.72
2	30	128	7.2	107	4.4	0.80
3	31	131	6.9	108	4.0	0.72
4	37	141	6.4	114	3.8	0.65
5	30	135	7.7	113	4.8	0.91
6	29	155	6.3	128	5.0	0.93
7	41	175	6.9	146	5.1	0.80
8	46	209	8.3	167	5.1	0.79
9	46	232	9.4	185	5.9	0.89
10	41	221	7.8	177	4.7	0.76
11	44	235	7.2	194	3.9	0.61
12	37	227	10.0	183	5.4	0.93
13	45	220	6.8	178	4.2	0.65
14	46	237	6.9	190	5.0	0.78
15	35	253	9.7	206	6.5	1.10
16	36	256	9.7	204	5.5	0.96
17	41	227	9.0	184	5.3	0.84
18	43	201	8.0	162	5.0	0.79
19	47	191	7.4	153	5.0	0.73
20	45	187	8.9	153	6.0	0.89
21	37	200	9.1	166	6.3	1.07
22	34	210	8.8	170	5.0	0.91
23	37	210	7.1	174	4.3	0.71
24	43	206	7.1	172	4.5	0.69
25	46	186	7.5	153	5.1	0.75
26	47	160	6.9	134	4.2	0.61
27	42	143	6.3	113	4.3	0.66
28	40	119	5.5	94	3.6	0.57
29	42	99	3.6	82	2.3	0.35
30	36	93	4.1	75	2.7	0.45
31	---	---	---	---	---	---
Means:		182.4		148.4
No. of Observations: 1187 No. of Observers: 68

Reporting Addresses

Sunspot Reports -- email: solar@aavso.org: postal mail: AAVSO, 25 Birch St. Cambridge, MA 02138; FAX (AAVSO): (617) 354-0665
SES Reports -- email: noatak@aol.com: postal mail: Mike Hill 114 Prospect St. Marlboro, MA 01752
Magnetometer Reports -- email: capaavso@aol.com: postal mail: Casper Hossfield PO Box 23, New Milford, NY 10959; FAX: (973) 853-2588 or (407) 482-3963

15	AAP	P.Abbott
9	ANDE	E.Anderson
12	ATON	A.Attanasio
16	BARH	H.Barnes
17	BATR	R.Battaiola
15	BEB	R.Berg
30	BEGM	M.Begbie
16	BMF	M.Boschat
14	BOSB	B.Bose
24	BRAB	B.Branchett
26	BRAR	R.Branch
27	BROB	R.Brown
6	CAMP	P.Campbell
20	CARJ	J.Carlson
19	CHAG	G.Morales
25	CKB	B.Cudnik
6	CLZ	L.Corp
22	COMT	T.Compton
30	CORA	A.Coroas
25	CR	T.Cragg
5	DEMF	F.Dempsey
25	DRAJ	J.Dragesco
23	DUBF	F.Dubois
30	ELR	E.Reed
11	FEEC	C.Feehrer
26	FLET	T.Fleming
24	GIOR	R.Giovanoni
13	GOTS	S.Gottschalk
7	HAYK	K.Hay
12	HSF	C.Hossfield
1	IMPR	R.Imperi
22	JAMD	D.James
5	JEFT	T.Jeffrey
13	JENJ	J.Jenkins
2	JENS	S.Jenner
28	KAPJ	J.Kaplan
15	KHAR	R.Khan
15	KNJS	J&S Knight
7	KUZM	M.Kuzmin
22	LERM	M.Lerman
13	LEVM	M.Leventhal
19	LIZT	T.Lizak
25	MALK	K.Malde
18	MARE	E.Mariani
30	MARJ	J.Maranon
19	MCE	E.Mochizuki
12	MILJ	J.Miller
25	MMI	M.Moeller
20	MUDG	G.Mudry
16	OBSO	IPS Obs.
19	RICE	E.Richardson
22	RITA	A.Ritchie
28	SCGL	G.Schott
8	SCHG	G.Scholl
4	SIMC	C.Simpson
11	STEF	G.Stefanopoulis
25	STEM	G.Stemmler
18	SUZM	M.Suzuki
15	SZAK	K.Szatkowski
15	SZUM	M.Szulc
27	TESD	D.Teske
9	THR	R.Thompson
25	URBP	P.Urbanski
16	VARG	A.Vargas
17	VIDD	D.Vidican
16	WILW	W.Wilson
6	WITL	L.Witkowski
29	YESH	H.Yesilyaprak

Table III. Means of Raw Group Counts (RG) and Ratios of Spots to Groups (S:G) in June 2001
Day	RG	S:G	Day	RG	S:G	Day	RG	S:G	Day	RG	S:G
1	6.1	3.4	9	12.3	8.9	17	12.0	8.9	25	9.7	9.2
2	8.3	5.4	10	12.9	7.1	18	9.9	10.3	26	8.8	8.2
3	7.5	7.5	11	14.9	6.1	19	9.2	10.8	27	8.2	7.4
4	7.1	9.9	12	15.6	4.5	20	8.4	12.3	28	8.5	4.0
5	7.6	7.8	13	15.4	4.3	21	10.3	9.4	29	7.9	2.5
6	9.1	7.0	14	15.7	5.1	22	11.4	8.4	30	7.1	3.1
7	10.6	6.5	15	15.88	6.0	23	11.6	8.1	31	---	---
8	11.1	8.8	16	14.3	7.9	24	11.2	8.4	Mn.	10.6	7.2

Click image to enlarge.
Fig.1 Comparison of Ri (provisional) and Ra estimates for June.
(Ri Source: http://sidc..oma.be/index.php3)

Smoothed Mean Sunspot Number (Rsm) for December 2000: 118.0

Click image to enlarge.
Fig.2 Monthly Ra and Smoothed Mean Sunspot Numbers (Waldmeier method).

Click image to enlarge.
Fig.3 Maximum, mean, and minimum Ra Values for Each Month from January 2000 to Present.

Editor's Notes

Errors in Reports
A significant number of errors, distributed over a relatively wide range of reporting parameters, were found in observer reports for June. Please be careful that your report contains the correct month and the correct ID code, and that the R numbers for each day are computed correctly. Please do not make any entries (e.g., zeros, asterisks, commments) on days when no observations were made. If you use the text version of SUNKEY on the website, remember that the dates in the header must be manually updated.

One additional request: If it is at all possible for you to report using SUNKEY.exe, its text version, or SolObs.exe, please do that. The information furnished in spreadsheet and word processor files must be recoded before it can be analyzed with the AAVSO software, and there is always the possibility that errors will be made during that recoding process.

Table I Column Definitions
Several observers have asked for definitions of the values included in Table I of the Bulletin. These are as follows:

Day: the cardinal number of the day for which data in the row are reported

N: the total number of observers who contributed observations on a given day

Raw: the mean of all R numbers reported on a given day

s.d.: the standard deviation of R values reported on a given day. Assuming a normal distribution of reported values--a reasonable assumption except when R values become very low-- the range from -1 sd to +1 sd includes approximately 68% of the reported R values, and the range from -2 sd to +2 sd includes approximately 95%. For example, given a mean of 100 and a standard deviation of 5, approximately 68% of reported values lie between 95 and 105, while approximately 95% lie between 90 and 110.

K-corrected: the mean of R values reported on a given day after the application of an accuracy coefficient to each observer's reported R. The k-corrected value is called Ra in Fig.s 1, 2, and 3.

s.d.: the standard deviation of the k-corrected values, with the same interpretation as above.

s.e.: the standard error of the estimate of the mean K-corrected value for a given day. The standard error is equal to the standard deviation of the K-corrected value for the day divided by the square root of the number of contributing observers (N) on that day.

Clear Skies
CEF

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