A Practical Guide to Lightcurve Photometry And Analysis

by Warner, Brian D.; Harris, Alan W.

• ISBN13: 9780387293653
• ISBN10: 0387293655
• Format: Paperback
• Copyright: 2006-06-01
• Publisher: Springer Verlag

Summary

The Practical Guide to Lightcurve Photometry and Analysis provides those with access to even a modest telescope and a CCD camera the background and detailed steps to take part in important astronomical research. Readers learn about the joint projects in which they can take part, as well as the techniques of gathering, analyzing, and then publishing their data. The primary market for this book is amateur astronomers, but undergraduate students will also find its easy going friendly style ideal for help with their studies in this subject. There is of course more to lightcurve photometry than simply taking pictures. For the results to be of value, the data must be gathered and processed in certain ways so that it is both meaningful and can be used by others for analysis. The book contains enough background material (theory) for the reader to understand - and avoid - the pitfalls in the process. More important, there are detailed examples provided for hpw to obtain data and, for many, the more exciting and rewarding effort of analyzing the data to determine various properties of the object being studied. Under "choosing the right software," the author looks critically at the commercially-available packages, providing screen shots and useful advice. Amateur astronomers who wants to go beyond mere imaging with a CCD camera will find everything ithat they need in the book to take a step into 'real' science.

Author Biography

Brian Warner has been an astronomer for 40 years. He ran the Minor Planet Observer for ten years, and has contributed more than 60 papers to the Minor Planet Bulletin, along with regular articles. He lives in Colorado, USA.

Table of Contents

Getting Started	1	(6)
What Is Lightcurve Photometry?	3	(1)
What Lies Ahead	4	(3)
Targets of Opportunity	7	(14)
Asteroids	7	(5)
Variable Stars	12	(3)
Eclipsing Binary Lightcurve Characteristics	15	(2)
Cataclysmic Variables	17	(1)
Cepheids	18	(1)
Long Period (Mira) Variables	18	(1)
Semi-Regular Variables	18	(1)
Other Targets	19	(1)
Summary	20	(1)
Photometry Fundamentals	21	(6)
A Little Bit of History	21	(1)
The First Color-Based Systems	22	(1)
The Johnson--Cousins Standard	23	(1)
Setting the Standard	24	(1)
Seeing Red	24	(1)
CCDs and Standard Magnitudes	24	(1)
Landolt Standards	25	(1)
Henden Sequences	26	(1)
The Photometry Primer	27	(20)
Instrumental Versus Standard Magnitudes	27	(1)
Air Mass	28	(1)
Extinction	29	(2)
Transforms and Nightly Zero-Points	31	(1)
Differential Versus All-Sky Photometry	32	(3)
Seeing and Scintillation	35	(1)
Matching Pixel Size to Seeing	36	(1)
Bias Frames	36	(1)
Dark Frames	37	(1)
Flat Fields	37	(4)
Photometry Apertures and Annuluses	41	(5)
Reporting Errors	46	(1)
Photometric Reductions	47	(30)
The Different Path	48	(1)
The Differential Formula	49	(1)
Clear to Visual Conversions	50	(1)
First-Order Extinctions -- Are They Really Necessary?	50	(2)
The Same Color Index	52	(1)
Transforms First	53	(1)
Finding Transforms	53	(3)
The Hidden Transforms	56	(1)
First-Order Extinction	57	(2)
Finding First-Order Extinction (Modified Hardie)	59	(2)
A Variation on the Modified Hardie method	61	(1)
Finding First-Order Extinction (Comp Star)	62	(1)
Comparison and Target Standard Color Index Values	63	(1)
Find the Color Indices of the Comparisons and Target	64	(2)
The Comparison Star Standard Magnitudes	66	(1)
Finding the Comparison Star Standard Magnitudes	67	(1)
Target Standard Magnitudes	68	(1)
Finding the Standard Magnitudes of the Target	68	(3)
The Different Path's End	71	(1)
A Minimalist Approach	71	(1)
Using the Minimalist Approach for Standard Magnitudes	72	(5)
Second Order Extinction	77	(6)
Deriving a Single-Color Approach	77	(1)
The Slope of Slopes Method	78	(2)
When Is the Second-Order Term Applied?	80	(1)
Summary	81	(2)
Telescopes and Cameras	83	(16)
The Telescope	83	(4)
The CCD Camera	87	(8)
Digital and Web Cameras	95	(1)
Filter Wheels	96	(1)
Guiding Considerations	97	(2)
Imaging and Photometry Software	99	(12)
Image Acquisition Software	99	(1)
Specific Features	100	(2)
Photometry Software	102	(4)
Conforming to Accepted Standards	106	(3)
Manual Versus Automated Measuring	109	(2)
Collecting Photons	111	(22)
The First Step -- Getting the Right Time	111	(1)
Planning the Observing Program	112	(1)
Selecting Targets	113	(1)
General Considerations	114	(1)
Asteroids	115	(2)
Variable Stars	117	(1)
The Observing Run	118	(2)
Measuring Images	120	(3)
From Image to Data	123	(2)
The Hands-On Approach for Measuring Images	125	(4)
Checking the Comparison Stars	129	(1)
The Automated Approach to Measuring Images	130	(3)
Analyzing the Data	133	(4)
The Quality of Data	133	(4)
Period Analysis	137	(24)
About Merging Data and Setting Zero-Points	137	(2)
A Simple Start	139	(3)
To What Precision	142	(1)
Refining the Search Process	143	(1)
The Amplitude of the Lightcurve	144	(1)
Aliases in Depth	145	(4)
Plotting the Half-Period	149	(1)
A Specific Alias Example	150	(1)
The Case of 3155 Lee	151	(1)
Period Analysis on a Spreadsheet	152	(5)
From Lightcurve to Shape	157	(4)
Building Star Systems	161	(12)
Getting Started	161	(3)
Binary Maker	164	(2)
The Many Possibilities	166	(1)
The Effects of Changing the Inclination	166	(2)
The Effects of Temperature Changes in the Primary	168	(1)
The Effects of Temperature Changes in the Secondary	169	(2)
The Effects of Changing the Mass Ratio	171	(1)
The Effects of Gravity/Limb Darkening and Reflection	172	(1)
Publishing Your Data and Results	173	(8)
Confirm Before You Publish	173	(2)
Asteroids	175	(1)
Variable Stars	176	(1)
Learn by Association	177	(4)
BIBLIOGRAPHY	181	(6)
GLOSSARY	187	(16)
APPENDIX A: CONSTELLATION NAMES	203	(2)
APPENDIX B: TRANSFORMS EXAMPLE	205	(6)
Example Transforms Data	205	(1)
The Spreadsheet	206	(2)
The Hidden Transforms	208	(3)
APPENDIX C: FIRST-ORDER (HARDIE) EXAMPLE	211	(6)
The Data	211	(2)
The Spreadsheet	213	(4)
APPENDIX D: FIRST-ORDER (COMP) EXAMPLE	217	(2)
The Data	217	(1)
The Spreadsheet	217	(2)
APPENDIX E: STANDARD COLOR INDICES	219	(4)
The Data	219	(1)
The Spreadsheet	219	(4)
APPENDIX F: COMPARISON STANDARD MAGNITUDES	223	(4)
The Data	223	(1)
The Spreadsheet	224	(3)
APPENDIX G: TARGET STANDARD MAGNITUDES	227	(4)
The Data	227	(1)
The Spreadsheet	228	(3)
APPENDIX H: LANDOLT/GRAHAM STANDARD FIELDS	231	(22)
APPENDIX I: HENDEN CHARTS	253	(32)
APPENDIX J: HIPPARCOS BLUE--RED PAIRS	285	(6)
Steps used to produce the List	285	(2)
Hipparcos Blue--Red Pairs	287	(4)
APPENDIX K: SDSS BLUE--RED PAIRS	291	(4)
Index	295