Event sampling from .xml

[astroSyvertHE]

How can I do event sampling from .xml? (gammapy1.0)

[bkhelifi]

Hello Sofia,
This is not supported, only the YAML format. Converters exit from XML to YAML.

[adonath]

Thanks @astroSyvertHE! Do you refer to the XML definition for the observations or the models? In both cases the answer is there is no direct support, but there are feasible workarounds. I'll ping @QRemy, as he has some experience with converting both.

[astroSyvertHE]

Hi,
I want to analize extended source with RectangleSkyRegion using reflected backround, but there's the error I'm not able to figure out:
WARNING:gammapy.makers.background.reflected:ReflectedRegionsBackgroundMaker failed. No OFF region found outside exclusion mask for dataset 'obs-20230324'.
WARNING:gammapy.makers.background.reflected:ReflectedRegionsBackgroundMaker failed. Setting obs-20230324 mask to False.

the code is:

The binning of the final spectrum is defined here.

energy_axis = MapAxis.from_energy_bounds(0.1, 40.0, 10, unit="TeV")

Reduced IRFs are defined in true energy (i.e. not measured energy).

energy_axis_true = MapAxis.from_energy_bounds(
0.05, 100, 30, unit="TeV", name="energy_true"
)

geom_on = RegionGeom.create(ridge_hess, axes=[energy_axis])

dataset_empty = SpectrumDataset.create(geom=geom_on, energy_axis_true=energy_axis_true)

dataset_maker = SpectrumDatasetMaker(
selection=["counts", "exposure", "edisp"],
use_region_center=False
)

finder = ReflectedRegionsFinder(min_distance_input='0.05 deg', max_region_number = 3)
center_pointing = SkyCoord(0,1, 0.02, unit='deg', frame='galactic')
regions, wcs = finder.run(region=ridge_hess, center=center_pointing, exclusion_mask=exclusion_ridge)
print(regions[0])
#print(wcs)

bkg_maker = ReflectedRegionsBackgroundMaker()#region_finder=regions[0], exclusion_mask=exclusion_ridge)
#safe_mask_masker = SafeMaskMaker(methods=["aeff-max"], aeff_percent=10)#10
safe_mask_maker = SafeMaskMaker(methods=["aeff-max"], aeff_percent=10)

dataset_on = dataset_maker.run(
dataset_empty.copy(name="obs-20230324"), o2,
)
dataset_on = safe_mask_maker.run(dataset_on, o2)

dataset_on = bkg_maker.run(dataset_on, o2)
#dataset_on_off = safe_mask_masker.run(dataset_on_off, o2)
#datasets.append(dataset_on)
display(dataset_on.meta_table)

Could you help me? thank you!

Cheers,

sofiav

[registerrier]

Here, what is happening most likely is that no reflected regions have been found because the size of your on region is too wide. If you are using a box of more than a degree across (as needed to cover the HESS GC ridge emission), it is likely that no reflected regions can fit without a very large pointing offset from the GC.
I think in this case, the reflected region is probably not the adapted method for such an analysis.

[astroSyvertHE]

Thank you.
I just performed the 3D analysis, but I'd like to use another method to see if the result I found is consistenti... So, the reflected background is not usable because the region size is to big. I suppose that also the ring wooble method is not useful, is it?

Thanks,

sofiav

[registerrier]

The ring background is usually used to correct the background of an image (not a cube). The wobble OFF region is similar to the reflected region but simply select regions at specific locations (namely symmetric positions w.r.t. FoV center). It will suffer from the same difficulties as the reflected regions.
For now, there is no background Maker except for the FoV background normalization for a case like this. But it does not allow extracting OFF counts to constrain the background.

[astroSyvertHE]

Hi,
I create an events sampling using the tutorial /analysis_3d/events_sampling, and in particular mutiple events sampling. Next, I used /starting/analysis_2 tutorial.

The error is:

KeyError Traceback (most recent call last)
Input In [36], in <cell line: 1>()
3 cutout = dataset_stacked.cutout(
4 obs.pointing_radec, width=2 * offset_max, name=f"obs-{obs.obs_id}"
5 )
6 # A MapDataset is filled in this cutout geometry
----> 7 dataset = maker.run(cutout, obs)
8 # The data quality cut is applied
9 dataset = maker_safe_mask.run(dataset, obs)

File ~/miniconda3/envs/gammapy-1.0/lib/python3.9/site-packages/gammapy/makers/map.py:395, in MapDatasetMaker.run(self, dataset, observation)
392 kwargs["counts"] = counts
394 if "exposure" in self.selection:
--> 395 exposure = self.make_exposure(dataset.exposure.geom, observation)
396 kwargs["exposure"] = exposure
398 if "background" in self.selection:

File ~/miniconda3/envs/gammapy-1.0/lib/python3.9/site-packages/gammapy/makers/map.py:176, in MapDatasetMaker.make_exposure(geom, observation, use_region_center)
170 if isinstance(observation.aeff, Map):
171 return observation.aeff.interp_to_geom(
172 geom=geom,
173 )
174 return make_map_exposure_true_energy(
175 pointing=observation.pointing_radec,
--> 176 livetime=observation.observation_live_time_duration,
177 aeff=observation.aeff,
178 geom=geom,
179 use_region_center=use_region_center,
180 )

File ~/miniconda3/envs/gammapy-1.0/lib/python3.9/site-packages/gammapy/data/observations.py:255, in Observation.observation_live_time_duration(self)
246 @Property
247 def observation_live_time_duration(self):
248 """Live-time duration in seconds (~astropy.units.Quantity).
249
250 The dead-time-corrected observation time.
(...)
253 where f_dead is the dead-time fraction.
254 """
--> 255 return self.observation_time_duration * (
256 1 - self.observation_dead_time_fraction
257 )

File ~/miniconda3/envs/gammapy-1.0/lib/python3.9/site-packages/gammapy/data/observations.py:244, in Observation.observation_time_duration(self)
238 @Property
239 def observation_time_duration(self):
240 """Observation time duration in seconds (~astropy.units.Quantity).
241
242 The wall time, including dead-time.
243 """
--> 244 return self.gti.time_sum

File ~/miniconda3/envs/gammapy-1.0/lib/python3.9/site-packages/gammapy/data/gti.py:170, in GTI.time_sum(self)
167 @Property
168 def time_sum(self):
169 """Sum of GTIs in seconds (~astropy.units.Quantity)."""
--> 170 return self.time_delta.sum()

File ~/miniconda3/envs/gammapy-1.0/lib/python3.9/site-packages/gammapy/data/gti.py:158, in GTI.time_delta(self)
155 @Property
156 def time_delta(self):
157 """GTI durations in seconds (~astropy.units.Quantity)."""
--> 158 start = self.table["START"].astype("float64")
159 stop = self.table["STOP"].astype("float64")
160 return u.Quantity(stop - start, "second")

File ~/miniconda3/envs/gammapy-1.0/lib/python3.9/site-packages/astropy/table/table.py:1874, in Table.getitem(self, item)
1872 def getitem(self, item):
1873 if isinstance(item, str):
-> 1874 return self.columns[item]
1875 elif isinstance(item, (int, np.integer)):
1876 return self.Row(self, item)

File ~/miniconda3/envs/gammapy-1.0/lib/python3.9/site-packages/astropy/table/table.py:246, in TableColumns.getitem(self, item)
236 """Get items from a TableColumns object.
237 ::
238
(...)
243 tc[1:3] # <TableColumns names=('b', 'c')>
244 """
245 if isinstance(item, str):
--> 246 return OrderedDict.getitem(self, item)
247 elif isinstance(item, (int, np.integer)):
248 return list(self.values())[item]

KeyError: 'START'

I used the same code lines of the two tutorials....

Thanks,

Cheers,

sofiav