{ "id": 74051, "title": "What is the unit of fluxes? And, are they fluxes at the observational frame?", "url": "/competitions/PLAsTiCC-2018/discussion/74051", "author_name": "", "post_date": "2018-12-07T23:51:35.627230600Z", "votes": 1, "comment_count": 11, "views": 0, "content": "

What is the unit of fluxes? \nAnd, are they fluxes at the observational frame?

", "messages": [ { "id": "435384", "postDate": "12/07/2018 23:51:35", "content": "

What is the unit of fluxes? \nAnd, are they fluxes at the observational frame?

", "rawMarkdown": "What is the unit of fluxes? \nAnd, are they fluxes at the observational frame?", "votes": null }, { "id": "436187", "postDate": "12/09/2018 20:16:01", "content": "

The flux unit, I think, is nano-jansky (1 nJy = 10−35 Wm−2Hz−1). It is the difference between the observed and template images. This is also the reason of negative fluxes.

", "rawMarkdown": "The flux unit, I think, is nano-jansky (1 nJy = 10−35 Wm−2Hz−1). It is the difference between the observed and template images. This is also the reason of negative fluxes.", "votes": null }, { "id": "436490", "postDate": "12/10/2018 12:12:55", "content": "

Just curious, what would you do if you knew what unit was used?

", "rawMarkdown": "Just curious, what would you do if you knew what unit was used?", "votes": null }, { "id": "436584", "postDate": "12/10/2018 15:25:18", "content": "

Funny, it seems I am not allowed to ask questions as I am down voted here. I suppose the one who did it only wants me to share but not to receive.

", "rawMarkdown": "Funny, it seems I am not allowed to ask questions as I am down voted here. I suppose the one who did it only wants me to share but not to receive.", "votes": null }, { "id": "436607", "postDate": "12/10/2018 16:22:22", "content": "

Sorry to hear about down voting. May be, someone just missed clicking it?

\n\n

The reason I asked about the flux unit is because there are more features that you can characterize by precisely calibrating the intrinsic brightness. For example, a superluminous supernova is brighter than -21 absolute magnitude by definition.

", "rawMarkdown": "Sorry to hear about down voting. May be, someone just missed clicking it?\n\nThe reason I asked about the flux unit is because there are more features that you can characterize by precisely calibrating the intrinsic brightness. For example, a superluminous supernova is brighter than -21 absolute magnitude by definition.", "votes": null }, { "id": "436612", "postDate": "12/10/2018 16:31:52", "content": "

Ty.

", "rawMarkdown": "Ty.", "votes": null }, { "id": "436621", "postDate": "12/10/2018 16:41:59", "content": "

No idea how to use this information. Maybe it can help you better convert flux to magnitude, provided some other infomation about the passband and template images, which we are not given or require more domain knowledge?

", "rawMarkdown": "No idea how to use this information. Maybe it can help you better convert flux to magnitude, provided some other infomation about the passband and template images, which we are not given or require more domain knowledge?", "votes": null }, { "id": "436626", "postDate": "12/10/2018 16:49:11", "content": "

Thanks for the answers. I wonder why we are not given the base flux and only the difference with an unknown base flux. This is why I asked how you would use flux unit info.

", "rawMarkdown": "Thanks for the answers. I wonder why we are not given the base flux and only the difference with an unknown base flux. This is why I asked how you would use flux unit info.", "votes": null }, { "id": "436631", "postDate": "12/10/2018 16:59:32", "content": "

It was me. I had also same question in my mind, sorry for misclick in a hurry instead of upvote.

", "rawMarkdown": "It was me. I had also same question in my mind, sorry for misclick in a hurry instead of upvote.", "votes": null }, { "id": "436637", "postDate": "12/10/2018 17:08:35", "content": "

Tx, I overreacted.

", "rawMarkdown": "Tx, I overreacted.", "votes": null }, { "id": "436645", "postDate": "12/10/2018 17:36:06", "content": "

Base flux is just a noise or galaxy template, and it is irrelevant. And yes, you will do a lot better with having knowledge in the field, I believe. For example, unless fluxes are calibrated properly, you cannot directly compare fluxes observed in the same filter with objects at different redshifts. Also, another question of this post is whether the given fluxes are in observal frame, this is also an important information.

", "rawMarkdown": "Base flux is just a noise or galaxy template, and it is irrelevant. And yes, you will do a lot better with having knowledge in the field, I believe. For example, unless fluxes are calibrated properly, you cannot directly compare fluxes observed in the same filter with objects at different redshifts. Also, another question of this post is whether the given fluxes are in observal frame, this is also an important information.", "votes": null }, { "id": "436674", "postDate": "12/10/2018 18:15:35", "content": "
\n

Base flux is just a noise or galaxy template

\n
\n\n

Not really, it is the flux measured prior to the period we have access to.

", "rawMarkdown": "> Base flux is just a noise or galaxy template\n\nNot really, it is the flux measured prior to the period we have access to.", "votes": null } ], "comments": [ { "id": 436187, "author_name": "lucaskg", "author_url": "", "post_date": "12/09/2018 20:16:01", "content": "

The flux unit, I think, is nano-jansky (1 nJy = 10−35 Wm−2Hz−1). It is the difference between the observed and template images. This is also the reason of negative fluxes.

", "votes": null, "replies": [ { "id": 436612, "author_name": "bkornpob", "author_url": "", "post_date": "12/10/2018 16:31:52", "content": "

Ty.

", "votes": null, "replies": [] } ] }, { "id": 436490, "author_name": "cpmpml", "author_url": "", "post_date": "12/10/2018 12:12:55", "content": "

Just curious, what would you do if you knew what unit was used?

", "votes": null, "replies": [ { "id": 436584, "author_name": "cpmpml", "author_url": "", "post_date": "12/10/2018 15:25:18", "content": "

Funny, it seems I am not allowed to ask questions as I am down voted here. I suppose the one who did it only wants me to share but not to receive.

", "votes": null, "replies": [] }, { "id": 436607, "author_name": "bkornpob", "author_url": "", "post_date": "12/10/2018 16:22:22", "content": "

Sorry to hear about down voting. May be, someone just missed clicking it?

\n\n

The reason I asked about the flux unit is because there are more features that you can characterize by precisely calibrating the intrinsic brightness. For example, a superluminous supernova is brighter than -21 absolute magnitude by definition.

", "votes": null, "replies": [] }, { "id": 436621, "author_name": "lucaskg", "author_url": "", "post_date": "12/10/2018 16:41:59", "content": "

No idea how to use this information. Maybe it can help you better convert flux to magnitude, provided some other infomation about the passband and template images, which we are not given or require more domain knowledge?

", "votes": null, "replies": [] }, { "id": 436626, "author_name": "cpmpml", "author_url": "", "post_date": "12/10/2018 16:49:11", "content": "

Thanks for the answers. I wonder why we are not given the base flux and only the difference with an unknown base flux. This is why I asked how you would use flux unit info.

", "votes": null, "replies": [] }, { "id": 436631, "author_name": "serdata", "author_url": "", "post_date": "12/10/2018 16:59:32", "content": "

It was me. I had also same question in my mind, sorry for misclick in a hurry instead of upvote.

", "votes": null, "replies": [] }, { "id": 436637, "author_name": "cpmpml", "author_url": "", "post_date": "12/10/2018 17:08:35", "content": "

Tx, I overreacted.

", "votes": null, "replies": [] }, { "id": 436645, "author_name": "bkornpob", "author_url": "", "post_date": "12/10/2018 17:36:06", "content": "

Base flux is just a noise or galaxy template, and it is irrelevant. And yes, you will do a lot better with having knowledge in the field, I believe. For example, unless fluxes are calibrated properly, you cannot directly compare fluxes observed in the same filter with objects at different redshifts. Also, another question of this post is whether the given fluxes are in observal frame, this is also an important information.

", "votes": null, "replies": [] }, { "id": 436674, "author_name": "cpmpml", "author_url": "", "post_date": "12/10/2018 18:15:35", "content": "
\n

Base flux is just a noise or galaxy template

\n
\n\n

Not really, it is the flux measured prior to the period we have access to.

", "votes": null, "replies": [] } ] } ], "raw_markdown_by_id": { "435384": "What is the unit of fluxes? \nAnd, are they fluxes at the observational frame?", "436187": "The flux unit, I think, is nano-jansky (1 nJy = 10−35 Wm−2Hz−1). It is the difference between the observed and template images. This is also the reason of negative fluxes.", "436490": "Just curious, what would you do if you knew what unit was used?", "436584": "Funny, it seems I am not allowed to ask questions as I am down voted here. I suppose the one who did it only wants me to share but not to receive.", "436607": "Sorry to hear about down voting. May be, someone just missed clicking it?\n\nThe reason I asked about the flux unit is because there are more features that you can characterize by precisely calibrating the intrinsic brightness. For example, a superluminous supernova is brighter than -21 absolute magnitude by definition.", "436612": "Ty.", "436621": "No idea how to use this information. Maybe it can help you better convert flux to magnitude, provided some other infomation about the passband and template images, which we are not given or require more domain knowledge?", "436626": "Thanks for the answers. I wonder why we are not given the base flux and only the difference with an unknown base flux. This is why I asked how you would use flux unit info.", "436631": "It was me. I had also same question in my mind, sorry for misclick in a hurry instead of upvote.", "436637": "Tx, I overreacted.", "436645": "Base flux is just a noise or galaxy template, and it is irrelevant. And yes, you will do a lot better with having knowledge in the field, I believe. For example, unless fluxes are calibrated properly, you cannot directly compare fluxes observed in the same filter with objects at different redshifts. Also, another question of this post is whether the given fluxes are in observal frame, this is also an important information.", "436674": "> Base flux is just a noise or galaxy template\n\nNot really, it is the flux measured prior to the period we have access to." }, "source": "meta" }