Transcript The Effects of Frequency Step Variation on H1 Observations of the

The Effects of Frequency
Step Variation on H1 Range
Observations with the SRT
of the Sun in Transit.
Robert Keeney
James McClinton
Renee Saucedo
Radio Astronomy
ST 562
Question:
How will varying the frequency steps
effect the data quality received from
the SRT while observing a given
source?
Step Frequency Graphic
0.04 MHz step – 0.02 MHz either
side of centerline frequency
25 total steps
Step Frequency Chart
Frequency Range
Step Values
0.005
1420.438 - 1420.563
0.01
1420.375 - 1420.625
0.02
0.04
1420.25 – 1420.75
1420.0 – 1421.0
1419.5 – 1421.5
0.08
1418.5 – 1422.5
0.16
0.32
1416.5 – 1424.5
1420.5 MHz
Purpose:
•To determine how the frequency graphs and
the generated images of the source produced
by the software are effected by varying the
frequency step setting.
•To find if there is an optimum step setting.
•To determine the limits and constraints of the
equipment and software.
Independent Variable:
Frequency Step Value
Dependent Variables:
•Frequency vs. Intensity Graph Resolution
and Distribution
• Generated Images
Constants:
•Time of Observation
•Source
•Software, Equipment, and Location
•Center Frequency
•Number of Steps on Either Side of the Center
Frequency
•Number of Scan Points
•Interference Sources
Control:
Default of 0.04 MHz to be taken every other reading.
Procedure:
1. Use an offset setting of 12 ° azimuth and 3° elevation,
centerline frequency of 1420.5 MHz and 25 channels
throughout the procedure.
2. At 11:30 am on Monday, 19 July 04, take a baseline
scan of the sun using the default settings. (Centerline
frequency 1420.5 MHz, 25 channels, step setting 0.04
MHz.)
3. Perform subsequent scans varying only the frequency
step settings to 0.005, 0.01, 0.02, 0.08, 0.16, and 0.32
MHz, with a baseline scan (0.04 MHz) in between each.
4. After each scan, take a screen snapshot of the
generated image and accompanying graphs, as well as
a screen capture of the frequency vs. intensity graph.
Results:
Baseline
Step 0.005
Step 0.01
Step 0.02
Step 0.04
Step 0.08
Step 0.16
Step 0.005
Step 0.01
Step 0.02
Step 0.04
Step 0.08
Step 0.16
Baseline
Step 0.04
Baseline
Step 0.005
Step 0.01
Step 0.02
Step 0.04
Step 0.08
Step 0.16
Step 0.32
Generated
Images
Step 0.005
Step 0.32
Radio Astronomy Lesson
Plan
Measuring the Wavelengths,
Frequencies, and Energies of
Laser Light by Diffraction
Patterns
Objectives:
•Students will calculate the wavelength, frequency,
and energy level of two separate laser beams by
measurements taken from diffraction patterns.
•Students will demonstrate an understanding of the
relationships among wavelength, frequency and
energy level of electromagnetic radiation.
•Students will apply algebraic and trigonometric
properties to investigate methods of calculating the
wavelength of light from a given diffraction setup.
Prior Knowledge:
Students will be expected to:
•understand that light exhibits wavelike
properties.
•be familiar with the concepts of single and
double slit diffraction, and interference patterns.
•be able to solve for a given variable in an
equation and determine an unknown angle
using trigonometric ratios.
Materials:
•Two lasers of different wavelengths
•Several diffraction gratings with different slit
widths
•Stands
•Rulers and meter sticks
•Wall or screen on which to project patterns
•Long (pointy) stick to jab students with if they
mess around with the lasers.
Procedure:
A lecture with a demonstration of a diffraction
pattern setup to include the following:
Discussion on the significance of the terms of

the equation:  
d
Relate the quantities of wavelength and
frequency through the equation:   c
Relate frequency to energy by the equation:
Where h is Plank’s Constant
(h=6.63x10-34J•s)
E  h
Diffraction Setup
Diffracted Light Beams
Laser
Diffraction Grating
Projection Screen
Diffraction Pattern Diagram

Students will be tasked
to derive the
relationship

  tan

1
by use and
understanding of this
diagram. (and sharp,
pointy stick persuasion
if necessary)


Diffraction Grating
Student Tasks:
Students will be broken into groups of two or three.
With the previous information, the groups will then be tasked
to develop a method to determine the wavelength, and thus
the frequencies and energy levels of each laser, using a meter
stick and calculator.
The above will be repeated for two additional diffraction
gratings of different widths.
They will additionally need to describe their method(s) in
written form and record their results.
Once groups are finished, the compiled data will be presented
to the class and the results compared to published data.
Teacher will monitor location of sharp pointy stick to assure it
does not fall into the wrong hands.
th
9
–
th
12
grade Math Standards
•Strand: ALGEBRA, FUNCTIONS, AND GRAPHS
•Standard: Students will understand algebraic concepts and applications.
•Benchmark: Represent and analyze mathematical situations and
structures using algebraic symbols.
•Performance Standards
–Simplify numerical expressions using the order of operations,
including exponents.
–Evaluate the numerical value of expressions of one or more variables
that are polynomial
–Know, explain, and use equivalent representations for algebraic
expressions.
–Solve formulas for specified variables
•Benchmark: Understand patterns, relations, functions, and graphs.
•Performance Standards
–Identify the independent and dependent variables from an application
problem.
th
9
–
th
12
grade Math Standards
•Strand: ALGEBRA, FUNCTIONS, AND GRAPHS
•Standard: Students will understand algebraic concepts and
applications.
•Benchmark: Use mathematical models to represent and understand
quantitative relationships.
•Performance Standards
–Use a variety of computational methods (e.g., mental arithmetic,
paper and pencil, technological tools).
–Generate an algebraic sentence to model real-life situations.
•Benchmark: Analyze changes in various contexts.
•Performance Standards
–Analyze the effects of parameter changes on these functions:
–Solve routine two- and three-step problems relating to change
using concepts such as ratio proportion.
th
9
–
th
12
grade Math Standards
•Strand: GEOMETRY AND TRIGONOMETRY
•Standard: Students will understand geometric concepts and
applications.
•Benchmark: Analyze characteristics and properties of two- and threedimensional geometric shapes and develop mathematical arguments
about geometric relationships.
•Benchmark: Use visualization, spatial reasoning, and geometric
modeling to solve problems.
•Performance Standards
–Solve real-world problems using congruence and similarity
relationships of triangles
–Understand and use elementary relationships of basic trigonometric
functions defined by the angles of a right triangle
•Guidance / Topics for Further Study
–Trigonometry allows a student to consider periodic functions.
–Students will be able to solve trigonometric equations
–Students will be able to apply trigonometric functions to solve
physical problems
th
9
–
th
12
grade Math Standards
•Strand: DATA ANALYSIS AND PROBABILITY
•Standard: Students will understand how to formulate questions, analyze
data, and determine probabilities.
•Benchmark: Formulate questions that can be addressed with data and
collect, organize, and display relevant data to answer them.
•Performance Standards
–Know the characteristics of a well-designed and well-conducted
experiment.
–Recognize sources of bias in poorly designed experiments
–Understand the role of randomization in well-designed surveys and
experiments.
•Benchmark: Select & use appropriate statistical methods to analyze data.
•Performance Standards
–Understand the meaning of measurement data and categorical data, and
of the term “variable.”
–For bivariate data, be able to display a scatter plot and describe its
shape.
–Describe and interpret the relationship/correlation between two variables
using technological tools
9th – 12th grade Science Standards
•Strand I: SCIENTIFIC THINKING AND PRACTICE
•Standard I: Understand the processes of scientific investigations and use
inquiry and scientific ways of observing, experimenting, predicting, and
validating to think critically.
•Benchmark I: Use accepted scientific methods to collect, analyze, and
interpret data and observations and to design and conduct scientific
investigations and communicate results.
•Performance Standards
–Describe the essential components of an investigation.
–Design and conduct scientific investigations.
–Use appropriate technologies to collect, analyze, and communicate
scientific data.
–Convey results of investigations using scientific concepts,
methodologies, and expressions, including: scientific language and
symbols, diagrams, charts, and other data displays mathematical
expressions and processes, clear, logical, and concise communication
reasoned arguments.
–Understand how scientific theories are used to explain and predict
natural phenomena.
9th – 12th grade Science Standards
•Strand I: SCIENTIFIC THINKING AND PRACTICE
•Standard I: Understand the processes of scientific investigations and
use inquiry and scientific ways of observing, experimenting, predicting,
and validating to think critically.
•Benchmark III: Use mathematical concepts, principles, and expressions
to analyze data, develop models, understand patterns and relationships,
evaluate findings, and draw conclusions.
•Performance Standards
–Create multiple displays of data to analyze and explain the
relationships in scientific investigations.
–Use mathematical models to describe, explain, and predict natural
phenomena.
–Use technologies to quantify relationships in scientific hypotheses
(e.g., calculators, computer spreadsheets and databases, graphing
software, simulations, modeling).
–Identify and apply measurement techniques and consider possible
effects of measurement errors.
–Use mathematics to express and establish scientific relationships.
9th – 12th grade Science Standards
•Strand II: THE CONTENT OF SCIENCE
•Standard I (PHYSICAL SCIENCE): Understand the structure and
properties of matter, the characteristics of energy, and the interactions
between matter and energy.
•Benchmark II: Understand the transformation and transmission of
energy and how energy and matter interact.
•Performance Standards Interactions of Energy and Matter
–Understand that electromagnetic waves carry energy that can be
transferred when they interact with matter.
–Describe the characteristics of electromagnetic waves, including:
origin and potential hazards of various forms of electromagnetic
radiation energy of electromagnetic waves carried in discrete energy
packets (photons) whose energy is inversely proportional to
wavelength.
–Know that each kind of atom or molecule can gain or lose energy
only in discrete amounts.
–Explain how wavelengths of electromagnetic radiation can be used
to identify atoms, molecules, and the composition of stars.
9th – 12th grade Science Standards
•Strand II: THE CONTENT OF SCIENCE
•Standard I: (PHYSICAL SCIENCE): Understand the structure and
properties of matter, the characteristics of energy, and the interactions
between matter and energy.
•Benchmark III: Understand the motion of objects and waves, and the
forces that cause them.
•Performance Standards: Motion
–Describe wave propagation using amplitude, wavelength,
frequency, and speed.
–Explain how the interactions of waves can result in interference,
reflection, and refraction.
–Describe how waves are used for practical purposes (e.g., seismic
data, acoustic effects, Doppler effect).